Unless this change was merged in a more vicious fashion when it was pulled from Ubuntu to Debian, the update in postinst should only be updating the default kernel version, not ALL of them, which seems perfectly reasonable to me. Pushing out bigfixes (and bugs too, since you want things caught quickly in sid after you screw up) immediately is a good thing.
... Adam -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]