I know we've discussed, at least within other topics, in the past.  Thought I'd bring it up as a stand alone topic.

What techniques do you use offhand?

I have always used the "jerk the trigger as you swing through the target" technique, more or less.  I try to not jerk the trigger, but pull steadily as I go across the target.  

Lately, in an effort to improve my offhand performance, I've been trying the "hardholder" technique, where I try to rigidly hold the target, and steadily pull the trigger, so when it goes off (usually a surprise to me), it's on the target.  

Using that technique with iron sights, I'm getting just over 10 m.o.a. 10 shot groups, with usually 6 to 8 within 7 m.o.a.  Usually two fliers open up the group.   My objective is to get to 5 moa consistently.    

Using the jerk the trigger technique, I think I get more center hits, but wider flyers.  I get smaller groups using the hardholder, but they're more random and less centers.

What are your techniques, and thoughts on the advantages of them?

This is from memory, back to 1994 when Jim Fern set the still existing 100 shot OH record at my Jefferson State Schuetzen Society match.

i believe he used a hard hold technique but, he dry fired in the house, every night for at least a hour. He then shot at least a brick of 22rf a week, OH. He was also big on having a rifle with as fast a lock time as was available. he shot a Miller. He said he would never shoot competitively with a hammer rifle.

Besides all that, he shot as many matches as he could get to from the NV area.

It's not something that comes easy and you have to have some natural talent, too.