As recently as a year or two ago I would have scoffed at the idea of ‘forcing’ a position as there’s an ideal time and place for every technique, and thinking otherwise was ‘bad’ Jiu-Jitsu.
So much for an open mind! =)
First things first, we can have injury(s) that prevent playing specific positions, so knowledge of how to creatively funnel people into other positions we can play is not only invaluable, but crucial training information to help keep ‘rolling’ alive.
Second, is the idea of survival and being able to protect ourselves first, mounting offense if necessary with limited resources.
So, in summary, for deep understanding not only do we have to figure out the perfect time for a position structurally, but also a number of ways of directing people into it.
I believe this ‘directing’ concept is one of the ideas that made Rickson’s Jiu-Jitsu so formidable, as I’ve heard multiple stories of him destroying a room full of Black Belts with the same move; a move everyone KNEW was coming! To my mind this was him training this principle.
Pedro Sauer ‘forcing’ a hand post with bridge instead of opting for the traditional one leg up/one leg flat mount bottom posture (setting up a possible arm grab for a trap and roll escape as well as other options like the shrimp escape variations discussed @ 0:00-0:30):