Your post is pretty spot on giggidy. Upon passing the ATP course though iCP cadets are placed in the same pool as Wings cadets.
To me the drawbacks of the iCP are that you don't get the 40,000 bond protection so the risk is solely on you rather than shared between the candidate and CTC as it is on the Wings course.
Secondly, with the iCP you don't automatically have a place on the AQC and ATP courses, you have to pass an interview to get on. I have been told the 'majority' of iCP candidates get onto these courses. But you are still essentially gambling your money on your ability to impress and pass this interview.
Thirdly, I would imagine that if CTC starts to have problems placing candidates the iCP cadets will be the first to suffer. They will simply not be accepted onto the AQC course at the end of their studies so as to keep the hold pool as small as possible.