Kim will know better than I do about Cherokee Purple (especially since I've never grown them

). But, I believe that harvesting early will help with the splitting, Lemon Tree.
My garden environment makes tomatoes especially prone to splitting

. I water with sprinklers, the soil is very porous, and I usually can only schedule irrigation on 2 days out of the week. It is also a dry growing season here.
Some tomato varieties will just split, split, split. So, I grow those that don't . . . or, at least, aren't likely to split.
After growing SunSugars for a half dozen years, I grew Sungolds to compare with them in 'o9. I didn't have much trouble with them splitting but other gardeners have complained about Sungolds and their splitting. What I did notice was that they have a little tougher skin than SunSugars. SunSugars almost never split.

A tender skin is no reason to expect a tomato to split. Yay

! In fact, the opposite may be true: the tender skin may have more "give" to it. I don't know.
Ruffled tomatoes DO seem to split more readily. I grow Thessaloniki, which is an heirloom but perfectly round. It just never splits.
I also grew Maltese last year and was real happy with it. It had only a small chance of developing splits. I think we could call its shape "oblate" but, whereas Thessaloniki is only about 7 or 8 ounces, I had one Maltese that was 1 3/4 pound. There were probably none as small as 7 ounces, so you can find large, old-fashioned heirlooms that aren't inclined to split. Thessaloniki and Maltese are early-ripening Mediterranean varieties.
I always enjoy talking about tomatoes

but I'm probably prattling on here because I'm afraid that Cherokee Purple will split in my garden and may not even have time to ripen, so I'm feeling deprived

. I should grow one called "Green with Envy" but it would probably split . . .
Steve