Ah, ok. You might be a human after all 
Honestly, I don’t think that your finger selection for the middle note creates a huge difference. Given that you feel equally comfortable with both options. If not, choose the finger which doesn’t strain your hand.
I’m not sure if it’s completely related but I have practiced four-notes-per-string scales when I was into Brett Garsed. This made me to use all fingers and each finger had a clear designation, no questions asked.
Oops! 
Same general point though, haha.
Interesting, so which is it?
I’m not convinced there’s a single right way.
I think the general consensus and Troy’s comments are spot on - in terms of single note lines, most people don’t find themselves as limited by the left hand.
So with super shreddy fast technical stuff, it’s just more often - but not always - going to be the pick that gives us problems. Then once you master a bunch of pick techniques you might find that the left hand does hold you back in some instances.
All that being said, I believe there are optimal approaches to different passages/licks, and some bits that have a few ways of accomplishing them. I also think there are some less used techniques by rock guitarists that are useful to get the hang of.
What’s nice is that for most of that we have classical guitar and all the resources that come with it. Those guys really have a lot of the left hand stuff figured out, and there’s a huge academic community continuing to try to move forward in this area and helps classical players reach new heights of virtuosity.
Personally, I like referencing classical guitar for most left hand stuff, then adjust as needed with rock influence (thumb over, bends, three fingered, etc) depending on context. With my students I have them set up in a mostly-classical way, though they aren’t classical lessons, and we deviate from it where it seems practical to do so, especially for bending and left hand muting, and hendrix chords, etc.
I have some injuries/overuse issues so I don’t push my left hand too hard, if anybody has tips specifically on endurance I’d be interested. The speed is there for most things, but I mostly play fast stuff in short spurts, not, for example, like 16 measures or two minutes of some blazing line.
It seems to me that there’s a Theory Of Constraints thing going on between fretting & picking hands where each one takes turns being the limiting factor at various points in our development.
Personally my speed playing the Eric Johnson stuff is limited much more by bad habits in my left hand. I’ve made some progress there, but it’s slow going because I don’t know what I don’t know.
Some sort of “best practices” for fretting hand probably exists and I’m just ignorant of it.
Paul Gilbert was asked in an interview, if either the left or right hand had a priority in development, and surprisingly he said the Left hand! He said your right is the gas, but you your left hand steers…
As great a guitarist and teacher that Paul is, he is just another master that Troy points out that is unable to explain the mechanics of his picking techniques in depth.
I think the key here is synchronization of both the left and right hands. If you have a highly developed right hand, and your left hand fingers “flail about” or hit the frets too soon, too late…
Your going to have issues with sloppiness in your playing.
The left hand fingers need to be controlled, the hand needs good posture, the fingers need to be close to the strings and move as little as possible.
Honestly, shoulder surgery was one of the best things that’s happened to my left hand dexterity in a while.
Try this - wrap some sort of mute around the nut of your guitar (I Prime’d a couple Gruv Gear fretwraps), fire up a backing track, and jam along tapping everything with your fretting hand.
Now, imagine ONLY being able to do that, for about a month.
Mad respect for not getting depressed and wanting to quit guitar 
I figured it was a great opportunity to re-learn how to pick - that’s why I’m here. 
After seeing your post about these I bought one for my main recording acoustic; it’s a godsend when playing things that are capo’d up.
The funny thing is, normally I think they’re silly and ridiculous, because they’re wildly popular in the djent scene. But, minus one hand and without a really good way to mute unwanted strings…
The ridiculous thing is the price.
Plenty of pros use something more like these, for one tenth the price (or even cheaper):
https://www.claires.com/ca/black--gray-and-white-scrunchies-163479.html?cgid=2745
To which all I’ll say is Amazon Prime and prescription pain meds.
Such as what? What about how to pick haven’t they explained?
This is very true. I could play very fast legato as soon as I learned 3nps scales. Feels like a very natural movement whereas picking is more inconsistent without correct technique.
One thing I don’t see a lot of people talk about is hand/wrist/thumb position in relation to the left hand. I wound up studying this heavily due to being diagnosed with Focal dystonia five years ago, of which I’ve mostly recovered from. My issue was in my index finger and 3nps fingerings became very difficult to play at moderate to fast speeds. 2nps were much easier, so my ability to do Greg Howe/Michael Romeo style tapping as well as pentatonic shapes literally saved my career… anyway…
I worked primarily with an instructor in Body Mapping (similar to Alexander Technique) named Jerald Harscher, who introduced me to the idea of applying a more violinistic left hand approach than the strict classical “thumb behind the neck always” approach. This puts the neck in a bit of a “cradle” between the thumb and index finger, and the fingers go on more of a diagonal to the frets rather than parallel. It keeps the wrist straighter and the forearm in a more neutral position. The player he told me to pay attention to in regards to a good “hand model” was Yngwie, who he described as having some of the best movements he’s ever seen. He also said this about Tom Quayle after showing him a video. Adapting this approach lead to a huge improvement in my left hand condition.
The irony is that many highly skilled players, despite going back to the “thumb on the back of the neck, fingers parallel” rhetoric, in practice almost never maintain this and do some amount of violinistic technique, especially bluesier players. I have only ever seen one shred instructional where the guitarist advocated explicitly for this violin style left hand approach and that was Borislav Mitic in his video that is available (for free, last I checked) on the www.dc-musicschool.com website. I’d really recommend checking this out as his description is pretty spot on.
I worked with
I mean, for one, they’re only really just getting into cross-picking now, so there’s a lot left to do there alone.
Maybe but I stated a while ago that to pick across the strings one can simply use a succession of TWPS changes. Besides, except for a small minority of cross picking licks, sweeping is a faster, cleaner and easier way to deal with playing arpeggios.
How many heavy metal or even rock licks in general call for string changes with one note per string that can’t simply be swept?
Maybe it’s different for bluegrass players but they comprise such a small portion of the CTC customers that spending too many resources, namely time and money, wouldn’t make good business sense for Troy’s company. I seriously doubt they have enough subscribers who are predominantly bluegrass players to make catering to them too much to be financially prudent. Hell, until CTC started covering playing arpeggios with alternate instead of sweep picking I only knew of one guy who did it - Steve Morse - and everyone I talked to about it replied: “Yeah, that’s Steve Morse’s thing.” In other words, it’s not a vital part of any great rock guitarists arsenal of techniques.
There are tons of licks that occur in rock and metal solos but almost none require to play one note per string at high speeds without the option of using sweeping. So to rock and metal guitarists, it’s a wiser use of their time to try to perfect their two way pick slanting licks and scales, their sweeping, and their legato techniques. Besides doing technique work on those three techniques, the best thing they can do with their time is songwriting and playing gigs
I think what Troy and his company have done to de-mystify how to successfully alternate pick, which was the reason Troy started CTC, is wonderful for people without the intuitiveness to learn it on their own, unlike all the guitar heroes of the 80s who never had something like CTC to rely on when they were learning how to play. Yngwie, Paul Gilbert, Shawn Lane, Satriani and the rest never had anything even similar to CTC and they achieved wonderful success, some of them while still in their teens such as Yngwie and Gilbert. That makes me somewhat annoyed when after Troy has already explained so much, there are people who still ask him for more and more directions on how to do even the simplest of things. I sometimes wonder if those type of people can figure out anything guitar related for themselves!
There is a tremendous amount of satisfaction to be gained in spending the mental and physical effort to figure out some things on their own rather than rely on someone else for all the answers. Not everyone has the talent to become a musician. If one finds himself asking Troy how to do even the simplest of things, after all the things he’s already explained to them, that’s probably a pretty good indication that while they may love music, they probably would be a lot more likely to achieve success by finding something that fits their God given talents better than being a serious musician does.
If people are asking questions it doesn’t mean they know nothing about that topic. In many cases I want to check if my way of doing things is efficient. Maybe someone has discovered a more effortless way etc…