Dear Savagebeast,
1. "I'm intrigued. Could you please elaborate a little more on fascia stretching? What is the best way to do it for biceps and triceps? Does it matter if this is done as part of your workout or between workout days?"
>>>> Fascia stretching entails the stretching of the fascia around the muscle. The premise is that the fascia provides neurological feedback to the brain, and once the muscle within the fascia hits the fascia, the fascia signals the brain to inhibit growth in that muscle. This probably stems from an evolutionary mechanism that prevented over-growth of muscle since more muscle = higher metabolism = less chance of survival in lean times.
To stretch the fascia, this entails hyperextending one's joints in order to elicit this. But I feel hyperextension should be avoided. Instead, I'd recommend getting as large a pump as possible, then stretching the muscle without hyperextending. The ballooned muscle from the pump will do well in stretching the fascia, much better than going into hyperextension with a non-pumped muscle.
For biceps, I'd do EZ curls and hammer curls or dumbbell curls as work sets. After that, a high rep warm down set quickly follows suit, and this would give me a pump 9/10 times. With the pump in biceps, I might sit on an incline bench, and with light dumbbells, allow my elbows to straighted without hyperextending. My whole arm would perpendicular to the floor. This gives the biceps a good yet safe stretch. Triceps is a little easier. I do close grip bench presses, skull-crushers and warm down with kickbacks. This never fails to get a good pump. I'd then bring my wrists to my shoulders, then proceed point my elbows upwards, such that my upper arm is at least perpendicular to the floor, with my elbows touching my head if possible. This gives the triceps region a good stretch.
And no, this need not be done on non-workout days. You can do this during your workout days. In fact, I usually do them after I finish my warm-down set, which is done immediately after my working set. You can do the same to chest - a set of high-rep dumbbell presses will give a good pump. We'd immediately switch to very light dumbbells, and with these dumbbells we'd do a weighted stretch using a dumbbell flye movement, dropping our arms to the sides as far as we comfortably can, then holding that stretch for 30 seconds or so. Increase stretch in the chest by taking deep breaths, expanding the rib-cage.
Coyote might wish to add the pump-stretch protocol to his workout days and also, slip-in the extra work-sets and pump sets on non-workout days just for his arms.
Then again, just try slipping-in two sets each for biceps and triceps like I suggested. See how that pans out for you.