Searched here and the web and find so many different opinions on tube amps and standby switches. I gather it is good to place the amp in standby mode when switching the power on or off. What about between sets or if the amp is not going to be used a few hours later? I was taught that the amp should be placed in standby whenever it was at rest and not being used. I was also taught that it was less stress on the tubes to leave the amp on and in standby even if you were taking a break for a few hours (as opposed to turning it off and then back on). Looking for some science on this one from techs and engineers. Amp in questions is an SVT-CL.