[Arran]

Or you can move that .015 uf cap to the radio side of the power switch and not worry about whether it's a safety cap or not since it will no longer be energized while the set is turned off.

Should it not still be an AC rated cap? If you make that switch and it has failed shorted, you still wind up a loud noise going "bump in the night".

How is a cap going to short out while it is open circuit at one end? If it is going to short out at all it will likely be while power is across it and that means the set will have to be on. I'm sorry but this whole safety cap arguement is getting old, I've owned over a hundred sets now, serviced almost as many, and I can't remember finding one with a shorted line cap even original ones. On the other hand I have had bypass caps blow in several sets and encountered shorted filter caps in even more, all were old ones of course. Also I've never had one I replaced fail, they were modern poly-film caps rated at 630 VDC, not AC rated but non polarized and more then ample for the job, if they were connected across the line full time then I would use a safety cap.
I've seen sets where the line cap blew but none that I owned or worked on, even witnessed it happen once, the set was turned on, cap went bang, blew the breaker, then went open circuit. Ironically this was in a 1950 Philco, and one leg of the line cap was on the radio side of the switch, nothing happened until the switch was turned on and both sides of the cap were energized. So one incident in one set in 20 years involving an original line cap and it wasn't my set nor was I working it, they are hardly the tinking time bomb they are made out to be. Use them if you like but to me it's kind of like wearing a crash helmet while driving a car.
Regards
Arran