I've trained BJJ for about 1.5 years, 1-2 times pr week.
When sparring, I sometimes pick lesser experienced students in order to practice attacks, and sometimes I pick partners that are stronger/more skilled than myself to practice defense and to challenge myself.
However I occasionally meet a purple, brown or black belt and am utterly destroyed and I get the feeling that these sessions are very unproductive.
I am immediately pulled into positions/guards that I have no idea on how to defend, and just do random stuff in order to not get submitted. These random movements are never remembered should they by some miracle work, as they are not in any context or related to any position that I'm familiar with. (Exaggerating a bit to make a point.)
Any offensive moves that I try are immediately negated, normally before I am close to finishing a technique. Passing guard or getting into sidemount or mount never happens.
Some of the high belts, put themselves in vulnerable positions and destroy me from there, this I don't mind as I get to practice the stuff I've already learned like passing and maintaining mount and so on.
But as explained above, other high belts just leave me with the impression that I've learned/practiced nothing after a roll. This leads to the initial question, was the roll unproductive or even a waste of time? If so, should these partners be avoided in order to learn more/improve faster?
Not sure if it's the best example, but how much would a novice chess player learn from playing a world champion?
Another: When beginning to learn to throw a tennis ball with accuracy, do you learn more from throwing at an object at 5 meters or the same object at 30 meters?