The fit between the neck and body on a set neck guitar is reasonably critical part of its construction.
It needs to be nice and snug to properly transfer vibrations between neck and body. Too loose and tone can and will be lost. It seems almost cli·ché in the guitar building community to take pictures of a mid-build guitar being held up by its neck before glue up with nothing else besides a tight fit between the neck and body to hold the body in place while suspended in mid air. I’ll admit that I enjoy looking at pictures like that. I’ve even taken a few. Ok I’ve taken a lot. It shows me that the craftsman can make a tight fitting neck joint. The funny part is that you don’t really want your neck pocket quite that tight. Super tight neck joints like that can stress the body unnecessarily and cause finish cracks near the neck pocket. It can also starve the joint of a set neck guitar of glue when attaching the neck to the body and actually weaken the joint. With that being said here’s a picture of the neck joint on the guitar I’m working on today.