You're pretty close. They have their ideas, spend days just doing bass sampling etc and then when it comes to actually putting a tune together it works alot easier. Hence why alot of their music sounds so clean. If a sound doesn't quite fit in there, get rid of it so the other parts of the track can breathe. Don't put a stab or woosh effect for the sake of it.
I can definately see why they do it though, cause you can sit there for hours just looking for that one sound that you may never actually find, there for stagnating the production process.