If you go to failure and then sit there and hold the weight, you're probably not going to get another rep. Rack it and wait the alloted time.
Rest-pause can have it's place, but if you're a relative beginner I think straight sets are better. It's certainly not required to increase size or strength. I would exhaust the "normal" training options before going into rest-pause. I would save it for something to pull out in a few years when you have a good base of training and need something to get the gains started again.
Agreed. I have been doing DC since January and it is definitely for advanced or experienced lifters. I have tried getting quite a few people to take up DC and many of them simply don't have the experience or drive to do the training. Creating a solid base of lifting experience/technique, along with the experience in having a solid diet and understanding your own body's recovery, are very important.
On a side note about rest pausing, it is simply dropping the weight, allowing yourself to catch a breath, in order to continue. Squats you don't have to be re-racked, just lock your legs out. I use the hammers strength machines for 1 of my presses( besides DB's) so there is no re-racking, just drop the weight. Flat BB bench is the only thing I can think of( incline too) you'll need a spotter for to re-rack. Also, rests need to be shorter, around 10 secs, 15 at most. At 30 seconds, the rest for rest pauses, and the theory of obtaining 20 reps off a weight you should fail at 6-8 reps with, is void. At that point you should just do straight sets. That is the point of rest pausing: doing a high rep set, with a weight you can only do about 6-8 times. Rest pausing allows you to hit 20 reps with that weight, and its still considered one set b/c the rest after each failure is very short.
I do a 5x5 for warmup, then the 20 rep set rest paused, so the potential for strength gains, and the muscles gains are both there. If you are interested search DC Training as there are many threads here on the topic. Though I do agree with SRS in creating a solid base first. DC has a lot to do with recording #'s and having the mental aspect for breaking your previous week's record. In fact, breaking all of your "records" is on your mind days before the actual lift, if you are recording everything properly. Its surely has opened my eyes in terms of dedication, and intensity.