In my experience, providing there has been no electrical or electronic equipment change in the vehicle, all should be well. If you have an owner's manual it should warn you if there is an issue in disconnecting the battery. Smells a little like BS to me too. As regards the hard reset for the radio, you ought to be able to get a detailed explanation of what they want to do for you before you commit yourself to their workshop charges. There are detailed procedures laid down for the dealer to follow.
Let us know how you get on.
Regards
Vdubbya
http://www.volkscity.com
P.S. please note that I said all should be well and not all will be well . . . . (smile)
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