What that will do is end up targeting whoever is on click3 and spamming them with cleases, etc.

If you want a smart cleanse macro, go:

/castrandom [target=char1] Cleanse,,,,
/castrandom [target=char2] Cleanse,,,
/castrandom [target=char3] Cleanse,,
/castrandom [target=char4] Cleanse,
/castrandom [target=char5] Cleanse


That will let you spam the button and you'll hit up everyone in short order. Of course, that also doesn't pass anything past it, so if you want adjust it a bit, put it at the begining of a /click button chain and add 5 commas after each cleanse, and at each click, 50% of the time you'll try a cleanse, 50% you'll pass to the enxt button.