Yep sorry, no logic really. To me though, unless it is tested and proved it doesn't work then just maybe it will work! Hence my suggestion to try a new tube. Can anyone suggest a way of testing the tube holder connections with a multimeter?(to save risking a new tube) The readings he should be getting? If the tube holder on the other side is working ok maybe compare outputs with the smokey one?
I guess I am a "if it aint broke, don't fix it" person! And no-one knows yet that it is actually broke. Plus I generally try to fix whatever I can myself before calling in the experts. Could the smoke have been from pcb lacquer etc? @Zaphod Beeblebrox would be the man who would know. I know I have seen pcb's smoke before but not necessarily burn out. Not sure videoing it all that time was a good idea but it was still smoking and didnt go "pop"
In saying all that, the most prudent advice (as suggested by yourself and others) would be to have it checked by a competent technician as even though it may still work, chances are there is now a weak link somewhere in the chain.