Is it a bad idea to use any kind of doe urine before the rut really kicks in?

Nope. Some does go into estrus earlier than you think - there are lots of bucks that cruise around, looking for those early in - heat does. Killed my first buck of the season this year :) very early (in the year) chasing a doe.

Let's face it....doe urinate all year round. The urine as a scent cover is not a bad idea, but using it as a lure to attract a buck to you will not be nearly as effective as when he's got the hots for her and is looking for her 24/7. If you are just out on a camera hunt and want to conceal your own scents, the urine will do its job. But if you are hunting meat to put a legal buck on the table, it will serve a much better purpose. Know what I mean? ;o)

No, the RUT refers to the main rut. Some does go in heat during the early rut. Others that dont go in heat during the rut (Especially Fawns) go into theirs lduring the later rut.

not a bad idea ,,, convidnice bulider um more than likley,,,,i have used tinks 69 and shot just as many busks pi nnn out or on a tree so there you have it some swear by it ,grunt calling it is the better of the interactive hunting i have seen and stalking while doing so is great

It's not a bad idea, but you might do better using an ambush method instead of attracting one.