When I pick up a weight my sole intention is to stress the muscle as much as I can with that particular set.
After warming up I then pick a weight I feel comfortable I can get at least 12 reps with.
During the set if 12 is going to be easy I slow down the reps and contract the muscle to try and exhaust it even further.
I really have no goal as far as reps and weight go, I just make every set count.
man we train the exact same.
I already 'know' what certain poundages will feel like, and the more I drop my weight and focus on the movement using just that muscle the better my body becomes. now I don't dumbell press heavier than 50's and my delts are benefitting massively. the more I feel the muscle work the lighter I can go and have an equally as strenuous a workout as smashing my body w weights I can't move just to support my ego.
as for sets. I have no idea. I just keep going till it's done. this depends a lot on my cal intake and activity levels the day before. some days I'm sure I bang out 24 sets for delts. chest I figure would be half that. today my chest wanted a beating. it wanted pressing movements not mamby pamby pec which I also like. so I bet I did prolly double my chest volume today. but this was strictly food/ fuel based from the day before.
I think most guys who have an impressive level of development are very in tune w their body, know how much volume per session to give it things like that. this kinda edges into that book I'm working on a bit in terms of being able to increase quite drastically just how much volume you can handle but in the end it comes down to listening to your body. know when to pound the sets, and when to throttle back.
great thread btw.