There is a video here of Kirby Allen shooting a whitetail with an excellent trail.....Very interesting! I wouldnt have thought of that.....
Steve reports it was an oil they used early on, and have since switched. Trails still present at range, but not as dramatic.
The video is unique in that it's a 100 yards. Most video of trails are at long range. Setting the target lower in the view gives you opportunity pick up the bullet earlier as it's drops into the FOV. As has been said slightly out of focus helps.
The appearance of curving is interesting, something in the photography??? Didn't key hole, how were groups?