This BAR MUSCLE UP TRANSITION PROGRESSION is great skill training modality to learn the proper movement pattern and build the strength. It can also be easily integrated into a workout so that you or your athletes can also get a feel for the stimulus as the workout is prescribed. 
WRAPPING YOUR THUMBS AROUND THE BAR - A big benefit of wrapping your thumbs is that it helps increase activation of the pulling muscle especially the lats. In a bar muscle the power comes from (besides your hips) the lats as shoulder extension drives you up and over the bar. Additionally, wrapping your thumbs is the safer way to grip.
The Hybrid Muscle Up is a combination of a standard bar muscle up and a gymnastics glide kip. It's beneficial to have alternate techniques at your disposal. The hybrid muscle up requires a little more skill to learn, and has a slower cycle time, but requires less energy to execute compared to a standard bar muscle up. When fatigued, being able to switch in out of techniques with gymnastics movements can be a key factor in being able to squeeze...