Joe Rogan lays it down on how to get better at Jiu Jitsu. The best way, according to Joe, is to strangle blue belts and choke the shit out of them. It's not to battle Black Belts when you're a white belt.
I think that's one aspect. But I always like training with higher level guys so that I can practice my defense. Then I like to spar with guys around my level so that I have to be tight with my attacks to secure a submission.
I come from the school of thinking that you should have training partners at your level, below your level, and above your level. Without one, you'll have to make adjustments to simulate it. That and drilling. I'm a believer in repetition.