I enjoy riding with both groups, passing in the corners in the white group is great, but on the same token, i realize that not everyone is ready to make a clean pass, not is everyone ready to be passed mid-corner.
With NESBA, I've learned more to "read" riders, learn their habits, and make a pass using more space, and drive on the exit of a corner, this makes me a bit slower in sections than some in TPM, but it is purposeful, as I do not want to be pushed off the track, nor do i want to startle a new-rider into making a mistake. However, on the same token, passing in a slower environment has made me less nervous to be passed, as i do not become unhinged at the sound of a motorbike screaming past me when i (feel like) am at a good lean angle.
To me, TPM's beginner group seem better suited for an aggressive street rider, whereas NESBA's beginner group is more catered to a rider wanting to go faster for the first time.
I've seen both NESBA days and TPM days in my respective groups turn into crap-fests, but its more about the individual riders, and not the overall organization. I've heard kubricky chew into a group and not allow passing in certain sections because of dumb decisions in the am, and I've heard froggy rip into a group on pit lane b/c of dumb passing decisions.
And in the coaching/CR regard, I've never had a problem grabbing a CR/coach and asking for a tow, of pointers on a line, as long as he/she wasn't previously commited to another rider. Theres so many people riding out there, it is hard to get individual treatment when a coach/cr has to look out for a totally new/potentially dangerous rider.
Bottom line is, both groups have their ups and downs, but its up to the rider to learn the most from the day. Both groups have awesome riders as coaches/CR's, I'm a member of both because i want to see the most tracks possible, and learn as much as possible from multiple sources.