great advice from Stu. I've been focusing on lateral delts for the past 2 weeks now and have seen a huge improvement from doing this. My split right now is: M- Lower body + 3 sets of lateral variation (+ 1 set till all out failure). T- Bench + assistant work. W- shoulder circuit consisting of 3 lateral and/or posterior head exercises (trying to minimize anterior). TH- Back FRI- same as Monday.
I know it looks like a ton of volume but I'm one of those guys who get little to no lateral head stimulation out of anything other than raises, so this has not negatively impacted my Bench/Back work. Keep in mind that the body adapts to large amounts of stress. This type of frequency is new to me and I believe it is what has brought the results. Once I stop seeing these results and/or it starts to effect progress in my other lifts, i switch it up.
After this I plan to get back into a heavier delt routine again and then i will probably go back to this, who knows. It's all about stressing the body in new ways inorder to get the response you are looking for.
P.S.- Get ahold of some BCAA for intra workout, I am a firm believer in using these especially with higher volume. A big part of the mondays and fridays delts work is simply getting blood/nutrients to the muscle!