Barry, many thanks for suggesting this book!. Don't worry, I have a
great esteem towards vacuum tubes and their underlying time-defying
principles (after all, the book is just 4 years older than myself...).
Power applied to the crystal by a tube oscillator is surely higher
than in an equivalent solid state counterpart, but 50's xtals were
also bigger (e. g. FT-243 format) and with metal contact plates that I
guess contributed to dissipate heat as a side effect.
Honestly, it adresses the crystal dissipation from a frequency
stability viewpoint, not quite my present concern, but I have found
interesting material in different chapters for other projects at home,
such as induction heating, and analysis of intermittent behavior. And
now I admit I didn't understand the principle behind the Miller
oscillator.
Ok, I will do some more experimenting and web search, and will
eventually post the results.