DataGuard and closed/cold backups

Well, I've R'd the FMs, and can't seem to find a clear answer - as I'm new to DataGuard, I need your help! :-)

I've been asked what the ramifications of doing a cold backup on a physical standby database would be, rather than taking the primary database offline. I didn't see anything in the docs that suggest this is a bad idea, but thought I'd check with the experts... In practice it seems simple, but will there be any issues starting up/running an instance off of the file copies, since before the shutdown it wasn't the primary?

Any help/advice you can provide would be appreciated!

Thanks,
Jackie

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