The fix on the lat. - lon. will not be off at all, since that is generated
from a radar return.

If the (secondary) radar return is late, would the position not be off?

The altitude might be 50 or even 100 feet off

It might be 10,000 feet off. It might be off by one bit (whatever that
would cause, depending on which bit). It might be intermittant.
Whatever. I do know that I've been instructed to stop mode C squawk on
occasion; whatever error I was producing at the time was causing
problems for ATC.

When you say that it would have been better (in this case) for the
transponder to be on, even if incorrect, you need to consider that you
don't get to know which plane is going to otherwise crash. You need to
do it for all planes.

Not just your plane. All planes. Everyone else who has a busted
transponder. Everyone else who figures that the rules don't apply to
them because they have a better idea.

This might not be a bad idea, but the unintended consequences should be
considered.

Jose
--
The monkey turns the crank and thinks he's making the music.
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