IMO, super-setting, drop-sets, forced reps, negative reps...these are all great tools to use down the road, when you hit plateus.
I don't even feel you should train to failure every session. its too hard on the muscles and mainly on the CNS.
The way I organize my upper body routines, I have roughly 2 per week (i'm on an 8 day rotation), one with a chest emphasis, and the other focuses on the back. On my chest day, I finish my routine with bicep focus, and don't target my triceps at all. On my back day, I end with triceps, and only hit the biceps very lightly, if at all.
Bi's and Tris' are smaller muscles, get used a lot, especially in compound back and chest exercises. Doing it my way, they still get hit twice a week either directly or by compound moves, and when I do work em directly, they aren't fatigued by a lot of compound moves so I get a more efficient return on my training.
Not saying this is ideal, just what I'm doing and enjoying so far.