I am pretty sure CT addressed this in an article back when the original layer system and the 10 day layer system came out but I am unable to find it. What is the optimal way to work up to and test your true 1RM in regards to how many sets, reps, and how much weight to add to the bar with each set? Using different versions of the layer system as they came out I successfully increased most 1RM lifts substantially but on my last attempt with Flat Bench Press I failed on 375lbs when my previous max just about 8 weeks earlier was 365. I started with 135x3 2x just to get warmed up and then added 40-50 lbs a set doing only 1-2 reps until I got to 375. Didn’t make it. I did the same for Back Squat on a following day and did get the lift without a problem.
I think you want to ramp up your CNS without inducing muscle fatigue. Jumps of 40-50 lbs are probably fine to start, but as you get closer to your max you will want to reduce the gaps of the weight jumps. You want to get your nervous system primed to fire all out, and I don’t think you can do that with 50 lbs less than what you want to attempt for your 1RM.
I can’t find the link, but there was an article I read on T-Nation about how to ‘trick’ your CNS into being ready to lift a heavier weight. Before attempting your 1RM, overload the bar with 5-10% more of the weight you are going to attempt to squat/ bench. Unrack the weight and just stand still/ hold the bar at lockout for ~5-10 seconds. Rack the weight and take your 2 min of rest and then attempt your 1RM weight. That method gets the CNS ready to fire on all cylinders and the weight will ‘feel light’ in comparison to the overloaded bar.
CT also gave a sample ramp up scheme in my thread last week about the layer system 2RM that might help you plan your 1RM scheme: