Garage spikes? That was in the original CTC series I think. If it’s happening on a “middle note” on a single string lick, there’s likely a setup problem…? Can’t say for sure though! All I can do is speculate and maybe try to imagine what I might be going through if I had the problem you are describing?
A good analogy to picking and I think Troy mentions this somewhere in the CTC archives is this thing that lots of us used to do with our bicycles as kids. Take a playing card, and set it so that it would flap across the spokes as you pedalled - It’s how you got that “dirtbike” sound! Thwap thwap thwap thwap!
So without being able to see or hear what you are playing (G-G#A seems pretty easy, but mileage can vary!) I have no clue what the tangle (LH, RH or both?) in this is being caused by, BUT…
I would suggest that if you can’t play a lot of repeating notes on a single string - then that’s the first hurdle/challenge. I myself tend to entrap my pickstrokes; I am a DSX player for the most part and thusly my pickstrokes are trapped on an upstroke, and should escape on a downstroke - however… for some reason I dive down after the downstroke. I’d like to say it’s because of background tension… But anyways, my trapped notes are still very quick, as I didn’t notice it until Troy and I scrutinized the footage at 120 FPS with a magnet. Tommo was pretty much ready to send me a bomb in the mail - I was driving him insane I am sure; this stuff is unbelievably complex. It really is. And you might be looking for a simple, simple answer (I know I am!) but the truth is that there are a LOT of solutions for any given problem I think and a whole ton of workarounds/cheats/hacks.
I guess what I am trying to say is that some problems are hard to identify even WITH video footage, so trying to help you without any footage is nigh impossible for the team I think…
But I am thinking that a great starting point might be
1-2-3-4—2-3-4-5—3-4-5-6—4-5-6-7—5-6-7-8—6-7-8-9 etc on each string, DUDU or UDUD as far as pickstrokes go; one will feel better.
The trick is to play it as fast as you can say it at first, accenting the first note of each group of 4, and play it as you say it. I can say it at about 120bpm fitting all four words in the time that elapses from the click
ONE-two-three-four-ONE-two-three-four-ONE-two-three-four
You could also work on 3’s in the same way:
1-2-3—2-3-4–3-4-5—4-5-6—5-6-7—6-7-8—7-8-9 etc
One could also take the LH out of the equation entirely and just pick open strings and see where that gets you; even NPS is always the most fruitful…
Good luck, I hope this helps somewhat.