Awesome work, and yes people don’t understand that aspect of 5/3/1 (or training in general). They think if they run higher weights in training that will make them stronger faster, instead of realizing the weights you lift in training are purely dictated by how you are responding & adapting to the lifting process.
You don’t lift heavier to get stronger. You GET to lift heavier BECAUSE you are getting stronger. You need to lift the right weight for the intended work effort, and it should progress over time if you’re successfully adapting consistently.
So they use their best possible lift for their Training Max instead of understanding it’s just an arbitrary value that helps dictate the numbers across the training cycle. I actually think about the kinds of weights I feel comfortable lifting for sets when I start it, then reverse engineer the TM off that. If I know I want my top set of bench to be 275-305 weekly to get stronger, I will take 305/.95=320 for my TM. Which is a weight I should always be able to take if I had to, even though I wouldn’t generally.