I'm not talking about switching to a different routine. The routine stays the same. All that changes is the weight; i.e. periodization.
I believe in progressive resistance, but I also believe that you will eventually plateau and weights will need to be cycled.
Let's stay I can add 5-10 lbs a week on my deadlifts. I'll do that as long as I possibly can, but at some point, my muscles and CNS just can't handle any more weight. So let's say I plateau at 735. The next week, I will drop maybe 70 lbs, and start the progressive increase over again, adding 10 lbs a week until a new plateau is reached.
665, 675, 685, 695, 705, 715, 725, 735. After 8 weeks I've reached my old PR. After that I usually have another month or so where I can continue to hit new PR's. But again, I will eventually reach a new plateau, but this one will be higher than the previous one.
20-40 lbs on your compound lifts in 3 months is nothing to sneeze at. Especially when you're already pretty strong.