Mark, I think we have a bit of miscommunication here. To my way of thinking and expressing myself, 'work sets' ARE your top set(s). So if you are going to work up to a 400x5 squat, that would be one top set, one single 'work set'. If you work up to 400 for 5 sets of 3, you are doing 5 top sets, 5 'work sets'.
For instance:
135x5
225x5
315x5
400x5
This would be 3 warmup sets followed by 1 top set, the 1 'work set'.
Or:
135x5
225x3
315x3
400x5x3
This would be 3 warmup sets followed by 5 tops sets, 5 'work sets'.
I'm happy you are feeling better but bummed that you ended up hurting so badly over perhaps miscommunication. As soon as I saw you had handled 5 sets of 3 for your 'work sets', I was instantly worried about your recovery.