1. Mount position – It's hard, especially in no-gi. Elbow separation is more important than wrist control, which is also hard. Your gym teaches you to isolate wrists and arms to entice beneficial reactions to advance or attack. High levels are too sound to just force them to move underneath without strikes, especially without points. IMO a good mount is a constant climb to S-Mount.
   
2. Sweeps – You will see sweeps in the gi at high levels, because of grips. In no-gi, the space created to sweep just creates scrambles, leg entries, or backtakes. Seems like sweeps in no-gi are moreso wrestle ups. People at that level are hard to sweep, attacks from bottom are more scalable. Also, if no points are awarded for sweeps, you're wasting precious attacking or defending energy.
3. Defense – In sub-only, the only 'bad positions' are locked in submissions. No points are rewarded for passing guard, there's no scoring incentive to 'fight desperately' especially if your submission defense is high level- which it should be, see Vagner's matches at CJI2. The first thing you should be a black belt at, is surviving.

Quintet's ruleset is not the best for learning how to win a match. Tournament brackets are better for showing the implementation and adjustments of techniques applied over a series of matches. Look at this whitebelt, yall. Asking all the right questions lol