Hard to narrow it down to one as there are many from different positions.  Big one from me is from one of my first instructionals I got from Tom DeBlass's half guard.  "Head over head, and hips over hips".  If playing the bottom half guard underhook game, am I forcing my partners head and hips over mine.  Success rate went up so much controlling the posture from there and let me down the path of diving into half guard for years to come.  

Adv. No Gi will be continuing on with the back attack block.  We will recap the straight jacket system and then move on to secondary attacks.  

Adv No Gi - Cont the back attack block.  Getting into the Straight jacket system.  Will learn a hand fighting system to trap your partner's arms and then be able to use all the chokes we learned last week.

Adv No Gi - Will be cont. with back control and getting into finishing mechanics of chokes and how to get them.Adv Gi -  Russ is on vacation so you get me this week.  We will be continuing with 50/50 and talking about getting into the legs and initial leg attacks.

Adv No Gi - 2nd week of the back control block will continue on keeping and recovering back control.  We can't do all the fun submissions, if we can't keep back control.  Hope to see you there.  

No GI Adv will start a new 2 month block with the new month.  Going to be looking at back attacks.  

Adv No Gi is a fun week.  I am back from vacation also.  Getting into some overback or octopus escapes.  If you haven't messed with that position before, don't miss out this Friday.

No Gi Adv. will be continuing on with the Pin Escapes block.  We will finish up far underhook escapes and then dive into the near underhook escape.