rizzlarolla used to check alphabetical naming and the close proximity of uids, but there's not really much point in doing that anymore. Even now, if you just look through 2 (most likely just one) pages of a person's post history then you'll know whether the account is farmed or not. But usually in that case, the campaign managers would probably outright decline the participants (if they're any good).
There isn't much point in checking alphabetical names (or some similar strategy) to find a single farmed account.
But...(!)
Once you find a single farmed account, there's a good chance that this type of strategy will reveal a shit load of other farmed accounts. Some of which might not otherwise become obvious for months/years from now.