Is being a "catch wrestler" different than being a BJJ guy that favors a top game vice guard? If so, how.
This is a good question imo.
A big difference between a pure catch guy and a bjj guy that favors a top game is the bjj guy that favors a top game has a bottom game that he can rely on if he is forced to play from bottom. That is perhaps the biggest difference because no matter how good your catch is there is someone out there who can put you on your back and its best to learn guard if that is the case imo. But I am pretty sure you are wanting to know if there is a difference in the way that they play top and the answer to that is yes.
Keep in mind that bjj has borrowed from catch also its not just the catch guys who have learned guard and taken from bjj so some of the stuff I mention bjj guys can do very well.
Takedowns is a big difference. Catch obviously has a much more elaborate takedown and takedown defense game. When the fight hits the ground bjj has a very good positional strategy that uses high percentage positions and high percentage submissions... pass, side, mount, and back. Catch uses those too but a practitioner might be more likely to branch off into positions and submissions that arent the game taught in bjj. For example if a bjj guy gets top position and has the back with the guy on bottom flattend out. He will just secure back mount and choke his opponent out. In catch you might see the top guy crab ride, come off to the side, cradle, neck crank, etc. Or if the guy is on his back and the top guy is passed the guard the bjj guy will use the common controls and submissions but the catch guy might use something like Barnett did against lister in a scarf type of hold, which in bjj is typically avoided due to the direct path to the back from the guy on bottom. But a good catch guy will use it and shut off the path with good control and even secure submissions from the position like Barnett did to Lister.
Catch also pays attention to pressure points and will use them in transition to set up submissions and make trasitions easier. For example passing the guard a bjj guy might simply knee slide while a catch guy might look to drive his knee into a pressure point or staple with a shin on a pressure point in order to cause a reaction. Or in side control the catch guy might dig some elbows into pressure points in order to get a reaction, etc. These are not some bull shit pressure point stuff either, they are effective techniques that et a reaction. Same with neck cranks. In bjj these might be looked at like "dick moves" but in mma or a fight for your life they are good to know.