I have no doubt that SOME FBO's can train as fast as ATP, and at less cost, agreeing with Aerospacepilot's post. You'd need to have a large fleet that included two or three twins, a large pool of CFI's, and a place where there will be no weather delays.
There is nothing special about how ATP operates, they are a big part 61 flight academy using 172's and Seminoles and have figured out how to get people to min standards as fast as possible. What they do at ATP could be done anyplace that can put a heavy emphasis on multi time.
The ATP owners fly around in a Citation giving "high altitude endorsements", they aren't stupid, but somebody is paying for that...
"The best part about flying at a local FBO is that odds are you will be flying with a quality CFI who got his/her ratings over a long period of time and has some good experience to offer. At ATP odds are you will be flying with somebody with very little experience..."
I agree. If I was at an FBO, I'd seek out a guy with some time. At ATP, the guy might be a gold seal but he still has never seen life outside the academy and has only been a CFI for three months. He also might be a guy who was a PPL 90 days ago.
That's my problem with ACPP. It's one thing to accelerate your training. It's another to take that and jump into instructing hard core. The FAA licenses and ratings are very much a license to learn. You can't expect much from a CFI who just got his "licenses to learn" in 90 days and now is your CFI.
There is nothing wrong with accelerated training. The problem comes when you don't take the time, between ratings, to use them, and gain experience from real world situations.