My restoration experience comes mainly from the old motorcycles side of things. The best paintjobs I've ever seen were done by Brits in a 6x8 garden shed with no power. These are the guys willing to put 5 coats on by brush and wet sand each one of them. Most people don't have that kind of patience, but if you do, the results can be worth it.

I think your technique needs to be determined by the results you want. Many Brit motorcycle tanks, for example, weren't sprayed or brushed, they were dipped. You can see the drips on the back side of the bottom. You can spray them or brush them but if you want the "original" look, you have to dip them. If you are doing an "original" restoration, you need to find out how they were done in the first place (probably on a rack with a paint gun) and do your best to duplicate that including hanging it from the same place so the missing paint inside the lip of the headstock is exactly the same. The tough thing about something like a bike frame is that you are going to get more paint in some places than others no matter what you do. I guarantee you there is some guy somewhere who knows HOW to paint a Paramount frame so he gets the extra paint in exactly the same places they did at the factory.

If all you want is a nice paint job, get a couple of rattle cans and a sheet and practice on a junk frame first!