Cheap diodes have slew-rate problems which can increase the noise floor in the amp. I'd use FREDs, and a time delay switch or standby switch. And recommend you precede each diode with a 100-ohm 5w resistor to reduce the turn-on surge. That simple trick can increase reliability of the power supply considerably.

It can cause damage to the tube's cathode coating. It is called cathode stripping. A problem mostly to power tubes running from plate supplies of 400v or greater. IMO, new current production power tubes are more prone to this than NOS.

>Do you mean that the tube rectifier wastes amplifier power or electricity?

It wastes electricity, adds heat to the system (never a good thing), and represents an additional stress on a power transformer.

>Can you wire the standby switch to become completely removed from the circuit after warm-up?

No. Why would you want that?

You wouldn't---it damages the coating and shortens the tube's life.
It leaves no other traces.

>Then only if the B+ is high, say if you are using 211 triodes or somesuch why is it an issue?

Only applies to oxide cathodes or oxide-coated filaments. Power tubes with thoriated filaments (like most 211s) are not harmed by it.

>the case of the surge circuit wouldn't you want all switches and/or relays out of the circuit

I don't agree in the case of COMMERCIAL amps. They have to be reliable and usable. You can wire your own amp however you wish. And accept any reliability issues that result.

>whatever happened to that nice PP 2a3 amp J. Eckland built?

He's still got the thing and it does sounds great--but not as good as the KT88 amp!

>When are we going to hear from Natalie Stone

Beats me--ask the publisher.