@jzohrab My playing has a few problems. I have a very fast tremolo picking, on good days I get to about 230bpm 16th notes (I think wrist, but not sure) more or less consistently, anything around the region of 200 to 210 bpm feels very relaxed and effortless. So I guess that is fine. But on a lot of other days I seem to “forget” how I do this. I will soon make some videos and show them under the technique critique section. I am tackling this problem for a few years now, it seems to be better now than it was about say last year or so, but still, this is quite frustrating at some point.
Also, I am having a question on the whole organizing part of this: Keeping a kind of journal is great and I will definitely try that again. I say again because I tried this before but never really knew what to record in the journal and how to practice properly. But maybe with the book (I feel awkward for calling a website a book because with books I always associate something physical, but I guess there is not really a better term lol) you wrote I will get to the point. But here comes the question I mentioned: how do I differentiate between technique and repertoire? For me, this is closely related. Let’s say I want to practice something of a technical death metal song which requires a very agile right hand with lots of string skipping etc… So working on the repertoire also requires working on the required technique, unless I slow the passage I want to learn down to the point that I only try to memorize it, but am not able to play it up to speed. Do you mean by practicing technique that one only focuses on something like tremolo picking in a very unmusical way? Because only “drilling” a technique without a musical context is kind of boring to me at least, and I know me: when I am bored, there is little to no progress because I lose interest very fast. But chances are that I just didn’t understand what you meant properly 
(I hope I explained well enough what I meant because that is kind of hard for me to do in English).
Thank you for the site and your offer. I read all of it for now and I am really intrigued and want to try this starting today. Here is what I came up with (although I guess it is slightly different):
Point #1: Starting out with some simple fretting hand warm ups for a few minutes. I definitely need to do this because if I jump into faster stuff right away my pinky starts to hurt at some point. I will definitely try the “exercise” from that classical guitarist you linked. I still have very large motions that I do with my left hand fingers, but that didn’t prevent me from doing faster stuff…but I think there is no damage done minimizing the motions. I think I will try to use my picking hand as little as possible for these few minutes, I will explain why in the next point.
Point #2: Jumping right into faster tremolo picking on a single string. Only bursts of six to ten notes. I noticed that if I start slow with my right hand the “forgetting how to pick”-thing occurs more often. But that definitely needs some experimentation. Points #1 and #2 should not take that long I guess, so you could think of them as a five to ten minute preparation phase.
Point #3: Using your suggested 20-minute phase to practice on a specific passage, let’s say I will practice that notorious descending sixes lick of the intro part of Technical Difficulties. I still have problems with that because of the downstroke escape. Cutting the passage into smaller pieces if necessary and trying the chaining you suggested (or any other technique to sort out what works for me). Resting after the 20 minutes and using the journal to note observations, progress, noting which technique I tried and how it went. Resting for a few minutes, getting a glass of water or a cup of coffee.
Point #4: If I have the time, repeating point #3 with another passage or even doing this several times with different passages, depending on mood and time on a given day. Even doing it later after a few hours passed. I should practice a single passage only once a day, I assume?
Analyzing the passages for what is going on musically should be done outside of practicing I think. The analyzing/studying part has nothing to do with practicing, or am I wrong?
Thank you so much, you have given me a motivational boost!
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