Let me be clear that I am not suggesting that everyone on this forum start doing a bunch of maximal work.
How to deal with a weak back or injuries..that is a whole nother discussion
Having an injury of course is different than avoiding one.
Let's just say we are making a lot of assumptions about where someone is in their training and whether they are healthy.
However, and this is going to sound like some really crazy stuff, just lifting heavier can be just as good for strength regardless of how heavy it is in terms of maximal ability. No matter what, you are putting just as much emphasis on counting reps and sets as form and quality. You are also assuming that you have to always reach toward a certain "rep maximum" to derive any benefit.
So here is the CRAZY statement. You can get stronger by lifting a heavier weight more times than you normally would using a "rep maximum" approach. I am not saying of course that you shouldn't do your volume training. I am only saying that you are making the assumption that the classic approach to volume is the only thing of use to you at this time.
Obviously you wouldn't try to take a weight you could lift 36 times in a 3x12 and lift it 50. But that doesn't mean that some good quality work at higher relative intensities, but not necessarily maximal ones, could be of benefit.
Getting back to the 3x3 example. Everyone assumes that volume and time, two secondary parameters, are just as important as intensity or workload. Now it may be true that there is a limit to how much benefit can be derived from workload but that doesn't mean that there is not much more benefit to be derived when your let loose the constraints of everything being a race to sets and reps. Most everyone can take a weight that they would use for 3x3, and lift it more times, for quality reps. Might that just be useful
. I know it is. I'm not saying you should do exactly that, Ross, it's just an example.