Stu,
I'll answer to the best of my ability/knowledge,
1) Even back then, I don't think that any DCI Level (World Class) corps wouldn't train somebody on the spot. You would have to be in the Cadet Corps, or a "Feeder Corps".
2) I didn't know that. Maybe there could also be a circut that would be less pit, amps, and other junk. Like Body Building, the new circut could be like "natural bodybuilding" (no steroids), and rely on the on field percussion voices, with little pit. It is nice there are other organizations of which to grow in.
3) I guess I'm a dinosaur in that regard. And can you tell me how many drum corps marching members go on to become ready for a "professional Career" in their chosen instrument?
4) Well, in 1972, I was trained to play cymbals. I spent time in the Seattle Imperials in the winter line from 76 to 77 and learned a lot. At that time, I could've played anywhere in the country. Back in the day, the corps had kids from the city/town of which they were from. Now, there are very, very many kids trying out for spots from all over the country. (And less corps from which to go.) One of my friends is an original Blue Coat, and he was a snare drummer. He went to see them in Boise in 2007, (or 08), but they treated him like royalty. The drumline asked him questions, and the drum instructor asked if he had questions as well. He asked. "How many people in this line are from Ohio?". The answer, 2.
So funding from the town may not make sense.
And since the activity has changed so much, from all the extras in the pit, to the philosophy of Movement being more important than the Music, (don't get me wrong, those kids work very, very hard. It's the staff who get's me worked up.) and the Kids have to be more athletes than ever. Although I would love to hear different sounding drum solos.
But, IMO, Cymbals should be part of the marching experience. If not, then why have musicians at all on the field. They all could be condensed in the pit with mikes, and the field could be all a Play/Production, etc.