To answer your questions Scott, one of the jump instructors there did tell me it was technically a HALO jump. The airfield/DZ is at about 6,000 feet MSL, and IIRC, anything past 12,500 you are supposed to be on supplemental oxygen. We never got that high. Just high enough for 10 seconds of free fall. Everything is graded and there were guys on the ground with very high speed cameras who video'ed your exit out of the aircraft, and kept video'ing until your parachute successfully opens. Then there are guys who grade your PLF. Then once you get back and get your chute all shaken out and hanging for the riggers to pack, then they show you your video of the exit out of the aircraft. Then they grade that. Then they show you your grade card for your PLF.
On my first jump, I actually instinctively went to "kicking and swimming" mode trying to grab anything to break my fall, then I flipped over on my back, then I thought "arch harder!", so I did, and I ended up in the proper position, facing earth, all the while keeping my count, and then pulled my "rip cord".
Nope, no 250 foot tower. We just had a building with probably about a 50 foot ceiling where we were winched up next to the roof, and then practiced "opening shock" , going through the emergency procedure checklists, like so many odd broken lines or a "Mae West" and how to rake out the line groups out of the reserves, and then finally we dropped from...oh, I dunno, 6 feet off the ground or so, to do a PLF in the pea gravel. We had done lots and lots of PLF's from wooden platforms of various heights into the pea gravel earlier in the week.
Nope, no fast roping. This was back in the early 1990's at Air Assault school. It was strictly ropes and rappelling back then. Stepping out on the skid of a Huey was always kinda awkward and spookey feeling.
getting back more on topic now... the catch with any sort of training is that the student knows he is in training or at a match. There is no element of surprise... there is NO moment like this ....

where you are trying to figure out just what the heck is going on before you decide how to react. Ya, know...that whole OODA loop thing.
I'm sure that split second where you are like this

or like this

brings about its own level of adrenaline dump.