I dunno about you, but when I work a specific muscle group (i.e. chest or shoulders) I am concentrating on THAT muscle's involvement primarily and it's contraction to failure. So, I get only an indirect pump to other muscle (i.e. triceps). So, I require further direct stimulation to triceps to thrash them into growth.
Skull crushers 3 heavy work sets/low reps
Overhead dumbell extensions 3 heavy worksets/low reps
Pushdowns 2 medium work sets/medium reps.
My tris are def growing right now.
rugger