ur triceps look like they are lagging more than your biceps. show us your current routine. i never liked DC training, you get strength from it but i never saw people make dramatic gains (size wise), but if u see results then by all means continue!

are you on any AAS? if so you can train arms twice a week every 3 or 4 weeks. for arms you shouldnt worry about how MUCH you can lift but feeling the contraction and getting as much blood into your arms as possible.

my routine is as follows:

pushdowns
skull crushers
barbell curl
preacher curl
hammer curl

thats it. 3 sets each 8-12reps. i get a nasty pump and then stretch then leave. just started this routine about 3 weeks ago and i def notice changes.