I think anything can be done given an individual of a decent level of intelligence and an amazing amount of desire. The thing is lets say you do have or develop perfect picth that doesnt mean you'll be a better musician you would most likely be a much better musician if you spent the equal amount of time developing relative pitch. I think the term "perfect pitch" means something else to each one of us and I fail to think that anyone of us would be a much more accomplished musican given the time to develop it. Intervals are the building blocks of melodys not the ability to identify a given pitch. The one who can identify a given interval(or all of them) will be much more "gifted" in regards to writing music.
When people refer to Beethoven they refer to his perfect pitch. I think we are overlooking the fact he most likely had an excellent relative pitch as well.
This is all from a person who did purchase the "perfect pitch ear training course" so before you invest the $150 on it take my advice to heart, DONT!!!!!!! I would recommend relative pitch though or the combination of the two, just not strictly perfect pitch alone, unless if you want to spend agonizing amounts of time to develop a ear training quality that may not even have the ability to be developed.
Good luck,
Thomyorke575