I don't know what 'bonk' training is. I do find I get good power gains in the summer when doing long (4-5 hr) group rides that generally include 30-45 min of all-out riding at the end of the ride when I'm in a glycogen depleted state. If you call that 'bonk' training then yes I do it. I don't think 'bonk' training implies what cyclists normally refer to as a bonk where one completely depletes glycogen.

I also do some two a day workouts in the summer and find these effective as well. I imagine the second workout of the day, normally a crit, is in a somewhat glycogen depleted state but I have no idea how much. The studies referenced above typically try and start with 50% depletion.