I agree with everything you say except for that last phrase. I do think you have to worry about being explosive if you want to raise your 1 rep max.
Your 1 rep is your ability to fire as many muscle fibers as possible right in that first split second off the bottom of your lifts. You obviously learn that by doing 1 rep maxes, but you can't do singles all the time.
But doing things explosively, I think, helps you get the idea across to your nervous system that you want everything available to work at the weakest point of the lift which is always the bottom (for raw lifters anyway). Your body in my opinion only uses what it has to use to perform, so with 70% of your max, it isn't working very hard nor very quickly unless you make it think that way.
I believe being explosive is important, but not that it needs a special day unless you are not naturally an explosive lifter.
For example I do not believe a guy doing 8x 3 with 70% "slowly" is going to really help his max bench any.
My opinions. I would love to hear what a Westside guy thinks, though.
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