Then, once they have done all that (two years in a row), if a team still wants them playing, they can then exchange their remaining active duty fo reserve time in order to finish their contract.
So yes, it is indeed true, that if Campbell and Viti show enough promise and put in enough hard work to make an NFL roster three consecutive years, then yes, they won't serve as officers or deploy overseas.
What about this rule though? It's difficult to get a feel for it. If a player were truly gifted enough to play football on Sundays, wouldn't he have been recruited by a major Division I program to begin with? Another interesting consideration is that academy cadets are able to leave after their first two years there, penalty-free.
So perhaps, instead of waiting until they have become seniors and going "oh, by the way, you can try and go pro if you want," they should be made aware of this from the get-go, so when they come to the end of those two years, they can say "I think I have a respectable shot at doing this sport for a living, I'm going to make the decision to transfer to a school where I can focus on it without the concern of signing paperwork committing to an officer commission and having to change it later, etc etc."
If West Point academy feels that this rule is necessary to help recruit the cadets they need to supply the active duty ranks with future officers, then I suppose I understand it. It would make a lot more sense to promote the two-year option, but this is the US military, and they can do as they please with the rules they have created. I'm not going to chastise these players for taking advantage of an opportunity that was given to them, but I will keep an eye on how, if at all, this new rule affects the Army's ability to meet its demand for officers in the future or whether it's simply an isolated incident of good PR generation.