misslifty:
- strength can mean different things in different sports
- in powerlifting, maximal strength is about generating maximal force.
- developing maximal force can be accomplished different ways. There is a range of views about what the best way is, hence we have a range of different training philosophies and programs
- arguably speed days, depending on how they're done, train power production and rate of force development, but this is not necessarily an important quality for powerlifting, where the test is maximal strength
- your theory relies on the assumption that "that's why a SPEED/XPLOSIVE day is included for each exercise in most successful powerlifting programmes". This is a non sequitur and it's false. Speed days are not in most powerlifting programs, let along most successful ones. DE days are in westside (but whether this actually constitutes "speed work" is up for debate as you use accomodating resistance). Light days are often in traditional periodisation programs, but not in all of them. There are no light days in any of the Eastern European training methods.
- there are alternative reasons why speed days might work for some people, eg active recovery, skill practice etc.
- I'm very skeptical of your claim that the majority of oly lifters you know can bench over 200kg.