Hello,
In my rebuild, I basically did a cleanup of the magneto, including bearing, insulating star, refinish stator and slip ring, etc., which had last worked 25 years hence. In the six years I owned the bike before that ('73-'79), four were spent diassembled or being reassembled by a shop. Who knows how much running time the bike experienced in it's 18 years between '55 and '73. So, if you think of time spent charging and discharging, it really is a small fraction of the time since new. Honestly, I'm not sure what this means for dilectric breakdown with time, but it seems to be working well right now. Considiering my history, now that I've said this, I have probabaly doomed myself to soon expereince a condenser failure and wishing I had Groily's armature handy.
Regarding having the work done by a shop or doing it myself, aside from the savings in money, which is not necessarily minor, I think that the more work I've done myself, the more connected I feel to the bike. This goes to our other topic wherein I said I can't comfortably leave it exposed to malice or accident. Soon or later I may have to face such realities but, for now, paranoia is the ruling force. I hope this is not taken as discounting anyone else's love of his (her?) machine, regardless of who built it or maintains it. Pardon the weak attempt at poetic philosophy, but "love comes in many forms" (with due deference to She Who Rules and has the form of first choice).
Richard L.