Interesting. I always leave radios off when I'm not planning on using them, but I've never really thought about it or tried to justify it.
I do make sure that transponder is always on Standby, even if only doing circuits. And I make sure my IMC students turn on, tune and identify all navaids, even if they're not planning to use them. But for a VFR flight, I don't bother.
Maybe based on the other replies so far, I should change that?
FFF
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