Don't just crank it on!

When someone actively resists your attempt to apply a joint-lock, most people fall into the trap of applying more and more force.  Besides being dangerous -- if it eventually works you may well hyperextend the joint -- this approach contradicts the "minimum effort" part of this month's theme.  Pretty soon you find yourself exerting maximum effort to minimum effect.

Three better alternatives:

1. Distract: A light strike or -- even the threat of a strike -- to a vulnerable will take your partner's focus away from their resistance for a moment, and that should be long enough to apply the lock.  [Other distractions: pinches, kiais, etc. can also do the same job.]
2. Change the focus of the lock: Most locks either use or have the potential for a two-way action.  Usually the resistance will arise at the point where you are applying most of the force.  Switch your emphasis to another point of contact (and maybe back again).
3. Flow into a different technique: Make use of the resistive force supplied by your partner to power the transition.  Now the resistance is working for you.

All of these options emphasize skill, sensitivity and knowledge over brute strength.

As the Borg of Star Trek say: "Strength is irrelevant. Resistance is futile.  We wish to improve ourselves."  

And Bjorn Borg (former tennis great): "You have to find it. No one else can find it for you".