The key here is the goal was to measure arm size. If this was a science project on making bigger arms, then it is beneficial. But I am not a science project.
I know doing curls helped me not have so many arm strains and doing triceps made my presses finish better/easier and I got stronger overall.
Arm size? I have no idea, nor do I care.
I am Anton Zdravko Martin!
Best meet lifts: Sq 150 Kg (330 lb), Bench 120 Kg (264), DL 160 (352) @89 Kg (197)
Best gym lifts: Sq 375, Bench 280 (pause), DL 385 @205 or less
Goals beyond my wildest dreams, 600 Kg raw total, 200/160/240
Hack away at anything which isn't essential. Do what you love, and do it often. Fazc.
Everything competes for recovery so more assistance is not always the best idea. miked96