Jab-I think I would have to disagree with you on that point
as a bad tube can bring down a amp if the design is not there to protect other components that maybe involved;if a tube shorts biasing resistors and/or caps may burn as well as tube sockets;level of damage can be a simple resistor to as melted area on the circuit board or tube socket.
as a bad tube can bring down a amp if the design is not there to protect other components that maybe involved;if a tube shorts biasing resistors and/or caps may burn as well as tube sockets;level of damage can be a simple resistor to as melted area on the circuit board or tube socket.