Personally I’ve only landed a few submissions in competition. I started thinking I really need to try to add one solid bottom submission to my game. Currently from the bottom I have success mostly with triangles (add in the occasional oma plata or open lapel choke from closed guard). To have more submission tools I think I really need to add a good choke to my a-game. Even a really succesful competitor told be that he is clearly more worried when the opponent has a submission oriented bottom game instead of a sweeping game.
Now I am in between trying to learn either the guillotine or the loop choke properly. I guess the guillotine is more versatile as you can apply it from more positions and use it in no gi as well. The thing is I think I currently understand the loop choke mechanics better so probable will be working on that one.
Christian Graugart’s blog (the former BJJ globetrotter) has great videos on both the loop choke and the guillotine that I am going to use in order to learn:
The Loop Choke (Oli Geddes version)
The "Icelandic" guillotine :)
Also…This week I had a morning practice where I decided to try to take every reasonable submission opening I got. This forces me to take little risks every once in a while and helps to get repetition for submission attempts.