Short answer: I have never done load development.
Longer answer: I have never had any interest in "load development". It seemed to be the opposite of what I have been trying to achieve. That is, executing each shot as best as I can. Shooting from a bench is fine when you're plinking but it's not nearly as enjoyable as actually working to make yourself shoot better.
Besides, I just asked the shooters that were winning matches what loads they were using in their rifles and copied that. Seemed easy enough.
Updated longer answer: With the
advent of optical sights in highpower, the relationship between the
shooter and his equipment, and the relative performance limitations have
changed. The rifle's sighting system used to be a limitation in the
shooter's ability to shoot small groups. Now, scopes have reduced that
limitation. As a result, the shooter can transfer more of his
marksmanship skills to the target. We can see this with smaller and more
centered groups.
Before optics, decent ammunition didn't expand the size of these groups.
Now, the groups may have shrunk to a size where even decent ammunition
produces variables that potentially expand the size of the group. The
question is whether the effort to improve that ammunition is worth the
incremental decrease in group size. I'm still trying to answer this
question.