The rest period thing isn't something you will always hear, and with good reason. Personally, I wouldn't do it as I prefer to be able to still move as heavy weights as possible even when cutting, and trying to skimp on time between sets will interfere with that M.O. The prospect of shortened rest periods starts moving into metabolic, or lactate training, which can be great for conditioning, but IMO less than optimal if you want to maintain maximum muscle mass.
Again, my opinion. I'm sure you'll find people who think otherwise.