Listmembers,
There are a few key points regarding chrome plating that weren't completely addressed, which I'd like to illuminate since the topic came up.
First, it is of prime importance to have a very good relationship with ones' plater if one expects excellent results while avoiding the pitfalls that can (but do not neccessarily have to) accompany a chrome plating job. The problem of drainage is easily solved by one of two methods. The best one is not to have any holes in the seat stays or fork blades in the first place. The only safe way to accomplish this is during the framebuilding process; filling the one vent hole in the fork or stay just after brazing the final joint that encloses the tube while it is still hot. Trying to fill a hole afterwards is risky and is a pretty good way to insure that a small pinhole will allow plating solution to enter and have no way to escape. So for resorations it is best to make sure each stay and blade hace two holes at opposite ends that are about 3/32" in diameter. Any GOOD plater can work with that and give the owner of the frame the ability to introduce a rust inhibitor AFTER the paint job is applied.
Regarding polishing. Yes it is dangerous, providing the plater (which includes all but the one I use) goes about it with the polishing lathes that Jim described. The exceptional plater will have developed a "secret" method to accomplish this task without risk to frame or human body. As luck would have it, the polisher at my plater is a good friend of mine (we have an interest in drums and drumming in common) and has passed this trick on to me; which I can use myself if I'm so inclined (which usually I'm not). But, it is quite safe and only requires some time and effort to accomplish, along with a few special tools and whatnot.
Only a really careless or inexperienced plater can accomplish hydrogen embrittlement on a frame. It's not easy to do. As far as I know, only about a half an hour at 300 or so degrees is required to disipate the effect. Maybe industrial (or "hard" chrome) requires 12 to 24 hours at temp., but not decorative chrome like we use. Modern nickel formulations take the place of the old "triple chrome" process and work perfectly well. Like Jim said, copper is for heavily pitted parts these days. If a frame is that bad off, it's probably best not to chrome (or maybe even ride) it at that point.
The chrome I get from my plater is mirrorlike; it's all in the polishing and keeping clean tanks.
As far as a completely chrome frame goes, OUCH! Costs a bit of money for a good plater to do it; so there's no point in doubling it by sending it to someone else to hand to a plater. Find you own guy and save the money for a payment on your Ferarri, like Joe said. Good luck.
Brian Baylis