Well, two weeks after fracturing the frame, it looks like I'm ready to start putting some pieces in it again.
Repair of the powder coat was sanding and featthering the damaged piwder coat areas, brushing on about four coats of high-fill primer, sanding and feathering the primer, then, three coats of gloss black appliance "epoxy" (they call it epoxy, but I'm not sure how that works without two parts). Not perfect, but more than good eoungh for tubes at the bottom of the bike destined for coverage in road grime, at least part of their lives.
Richard L.