#1
i know this has been asked millions of times but is tuning guitar down to drop d and drop d flat bad for neck.

I usually tune it to these then when finished put it back to standard.
#3
It will have no effect. Tuning down to drop c, drop b, etc you'll have to setup the guitar.
Jackson DK2M
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Yahmaha El-Cheapo Acoustic

Randall G2
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Behringer 4x12 Cab

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