I've tried it several times and am just now getting it right. It adds time to veg and can't be done (easily) with clones are the main downfall. Here are some pictures of Jilly Bean being mainlined.
Here they are after their first training session. They have been topped once previously. Clones were taken at this stage. There are some auto flowers flowering in the back.
A week or so later they have been topped, trimmed, and trained for eight tops.
All training is done and they are about ready to flip to 12/12. The auto flowers have been removed.
After about a week of flowering. The males have been removed and the clones taken previously are replacing them. That was about a week ago.