Rob I totaly understand the length argument. It makes it easyer to enforce but you have to admit my little baits(gills, baby bass,trouts) are true swimbaits in every sence. They are also big fish producing baits. The problem is where do you draw the line.
If it was a length only and you accepted a punker or a big tube the why not a ten inch worm. After all a punker is a top water walk the dog bait and a tube is still a tube regaurdless of how big it is. There is no cut and dry easy way to do this. Seriously if it were me running the tournament and I was unbiased I would put together a panel of 3-5 guys and accept or deny each bait on a bait to bait basis. I would be much more lenient on bigger baits but I would allow some of the smaller baits with proven big fish ability.
I would have a date set for anglers to submit any bait for aproval that was not on the first list well before the date of the event. Then once the aplication date was past no other baits could be submitted. At that point you would judge each bait and publisize your official list. If one of the anglers didnt get his bait in before the deadline he would have nobody to blame but himself.
For the actual judging of the baits, I think you would have to consider a few things. Larger baits that are considered swimbaits would be easy. The hard part would be the smaller baits. I would think my baits would be right about the cut off.

www.mattlures.com