Thanks again and I think I've put my finger on my Proton issue.
#1, the battery did need to be replaced. The CB1 is supposed to "see" 9V. I know from a past experience that it will still function when the battery is down as low as 6V (perhaps lower, but I once reached and then measured 6V from the battery so that's my "tested" lower voltage limit) but the tone/output is affected. Replacing my battery made an audible difference (it also let me ease back at least an "hour" on the Proton's gain pot). I also very slightly raised my PUP heights which helped, too. I'm definitely not now having issues triggering the effect.
My issue - to the extent I actually have one, maybe the problem is my own in that I just haven't practiced enough with the effect to adapt to how best to pick with it - is not with the triggering, it's with the decay. This is a guitar I've never had any sustain issues with before whatsoever but with the Proton the guitar's notes - not the effect's decay frequency level but the overall decay of the guitar's own output - are not sustaining as long as would be ideal for this specific effect. At least that's what I'm hearing/feeling.
With my Line 6 M13's Tron Up model, as noted previously, I'm preceding the effect with a compressor. I set it up this way primarily to limit my upper volume threshold to avoid sharp and unwanted high transient peaks. But now that I've analyzed it further and A-B'd it with my Proton, it's clear to me that the comp is also serving as a sustainer - it's keepin my guitar's signal active longer than it would be without the comp (where it fades out faster) and this is a big help with using the Tron Up model.
Not sure what my next step will be but at least I feel now that I'm better understanding what I'm working with in this regard. (This experience has also benefited me in that, as a result of it, I've gone back and revisited several other aspects of my rig that I hadn't changed in a long while, making some [I hope!] further positive adjustments.)
One followup question I do have is did Jerry precede his MuTron with any effect (turned on, obviously) that would have served as a sort of "sustainer?"
P.S. to waldo: Just want to confirm before ordering - the regular Jerry version of your buffer, i.e., the not-unity-gain version, am I correct that its output is slightly less than unity?
When we Go to Heaven, will Jer ask whether we were the perfect Jerry ... or whether we were the perfect us?
What does Jerry tone mean to you? Copying Jerry slavishly? Honoring Jer's music no particular way but our own?
We're each of us unique. And also the same. Can we open our hearts and minds to both?