the palmer has absolutely nothing to do with the tube failing.
simply running an amp hard, does that.
the palmer does not directly effect the way the amp works.
it would do the same thing if i ran it the same way without the palmer.
you are thinking of the Weber Mass Lite attenuator i run the mesa into.
the palmer is strictly a full signal-to-line level device.
again, the weber has nothing to do with the way the amp works.
this is a misconception about attenuators, that they harm the amp.
they are only a load...
the only thing that harms amps, is load imbalance, or running it hard...
as it is, the new tubes sound awesome.
and since they were about 10 years old, and had the weber in line with the setup for about 5 of those, i'd say that's a resounding success story.