I bathe my sphynxs before every show. When we have 3 day shows I only bathe them the first day of the show. I do the touch ups the rest of the days. When I showed Ty we wiped him down with chamis. I think it depends on the breed of the cat what you do before the shows.
I have always bathed the cats before a show. I want them at their very best. The only time I might not do it would be back to back show weekends, but I've never done back to back shows. I usually do 1 or 2 shows a month (usually one), and the shows are 2-3 weeks apart.
I bathe my guys, but I have different bathing rituals depending on the needs of an individual cat's coat. Some need a lot more work than others. . . and I know of some kittens that consistently took "Best" without so much as a wipe-down.
Some cats are just naturally blessed with the perfect coat for their breed. I think the great challenge in showing a patterned cat is finding a bathing technique that best enhances that cat's pattern. With some cats, less is more.
I've done a number of back-to-back weekends. Sometimes even 3-4 weekends in a row. When showing that much, you have to be careful to make sure that the shampoos are not so harsh that they damage the coat and that your conditioners/texturizers do not leave any build-up.
I honestly think any cat can be enhanced by a bathing routine; the key is to find the right combination of shampoos/texturizers/conditioners. It's important to consider what type of coat your cat has. . . dense and resiliant? Light and fluffy? Coarse? Is the hair close lying to the body like an oriental, or is it much longer? And what type of coat should your cat ideally have? All of these things must be taken into consideration when deciding a bathing routine.
Pet store shampoos are not usually going to cut it; I've found my cats looked and felt worse after using them. I personally feel they are a waste of time and money. Use the shampoos that are carried by show supply stores, like Cherrybrook. http://www.cherrybrook.com/ They might seem more expensive, but the results will be far superior.
In order to evenly distribute heavier shampoos and conditioners, I'll dilute them in water about 20:1. I'll sometimes use de-greaser in areas that are prone to clumping and greasy build-up. (Chest and neck, armpits, base of tail, and the tail itself) You'll have to replace the oils that were stipped out with a light conditioner/texturizer, because otherwise the hair is going to be so clean that it breaks apart, and in a patterned cat, this can really destroy the overall effect.
It's also important to rinse, rinse, rinse in order to remove any residue. Sometimes a vinegar rinse is helpful before your conditioning/after bath treatment, but lately I've been favoring other products.
I've also given hot oil treatments to a SH
And I've used deep conditioning treatments immediatly prior to bathing (not after, might have too much residual build-up)
I do bathe my BSH(s) before shows. The hair needs to be standing away from the body and using a silver shampoo (I mix regular pantene ice shine with silver shampoo for cats together) makes the color look brighter and better. If I had dark or blue BSHs, I propably wouldn't bathe them (the coat texture is usually much better on them).
Interesting - if my new Ocicat is chocolate silver or silver (the breeder says the choc-silver would turn out better as the silvers tend to fade too much), then I'll keep the Pantine Ice shampoo in mind to mix with the cat shampoo. I used to use Nexxus Simply Silver on my white Cornish Rexes and it was wonderful - better then any cat shampoo!
If need be I bathe them appr. 4 days before a show. I breed Devon Rexes and if I bathe them the day before the show, their curls won't have time to develop (the more you pet a devon, the better the coat
Since I usually keep my cats in top condition I don't always have to do anything before showing (and still get compliments on the grooming).
I have bathed the bengals prior to a couple of shows. Total waste of time. Their coats don't look any better. As a matter of fact, I would risk making them look bad if I didn't rinse well enough.
Bengals need only a chamois rub down between rings and some anti-static spray if it's winter time.
Now our Maine Coon is a completely different story. A 3 hour bath/drying session prior to each show was an absolute must. Then lots of combing and grooming between each ring.