I must admit I've just completed the first month of Waterbury-inspired TBT and been really impressed with the results. I have shunned TBT for years in favour of body part splits. However, I do much more conditioning work now through my interest in martial arts, and it appears to fit better with that (which is perhaps why he trains a few well-known fighters). IMO, one of the biggest factors is the undulating periodization aspect, i.e. mixing up rep schemes every workout. This shouldn't have surprised me as I had a similar experience following an Alwyn Cosgrove plan, which was an upper/lower split, and ran for 6 weeks before the exercises were switched up. I had a lovely feeling of light DOMs after every session until week 6 when, lo and behold, the gains stopped, hence the change up! The same is happening with TBT.
Also, the TBT fits well for me doing two sessions a week; one follows a 10x6 rep scheme; the second is 8x10 (generally Mon and Thurs). Done as circuits, with some ab work and pre-hab to finish. On top of this, I will try and do another 3-4 sessions with at least one day on sled work, i.e. eccentric-less lactate training; and one strongman sessions; the other 1-2 will be skills-based or fight drills.
Coupled with my Indigo, this is a really good first month for fat loss on this system.