I train a lot like Dorian Yates. I train to failure so I can truly see where I am strength wise. When it comes time to train for the next workout, I will add weight. Here is an example how I train:
For the last set:
Workout 1 - Incline Barbell Presses 300lbs x fail at 5
Workout 2 - Incline Barbell Presses 305lbs x fail at 4 + 2 forced
workout 3 - Incline Barbell Presses 305lbs x fail at 5
Workout 4 - Incline Barbell Presses 310lbs x fail at 4 + 2 forced
Workout 5 - Incline Barbell Presses 310lbs x 5
Workout 6 - Incline Barbell Presses 335lbs x 3 negatives
If my strength starts to stagnate after a period of time, I will change exercises and use weights where I can fail at higher reps 8-12.
I keep a training log to monitor the weights I use. I think training to failure recruits tons of muscle fibers, therefore you require less sets. Thats my opinion and what works for me. I think when you use a 5 x 5 program, you are actually able to get at least 8 reps for the first set, then 7 for the second, and etc. When it comes to squats, I will get as many reps as possible, then I will use the rest pause method to force out a few more. Sometimes, on my last set, I will put on 225lbs and will squat for 4 to 5 minutes straight just to shock the lower body. I believe that Tom Platz did something similar, except he squatted for 10 minutes straight

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