Here is my process. On dark colored jobs, I repair any body problems that I can find, trusting my hands to find them....not just my eyes. They will "lie"!

I go through the prime-guidecoat-block process twice.

The first prime, I use a long board with 150 on flat areas, and glaze in any problem areas until I can run the palms of my hands over it without feeling humps or flats.

I them reprime & guidecoat, and block with smaller stiff pads using 360....glaze any problems....touch up anything I can find, then run my hands over it again.

If it feels good, I seal and paint, watching for problems that won't be covered during the final blocking & buffing on the finish.

If you do miss a spot, do what you have to do to fix it, so you will be happy with the finished job.