How big can clones be?

Just curious as I've seen Dr. Greenthumb recommend taking large clones from his Iranian if doing it in that style. So how big can they be and still survive?

I wouldnt think you wouldnt want them to big im not 100% sure on this but it would seem the more leaves on a clone, the more surface to transpire water out of them, and the higher chance they have of going limp and dying.

to big and they have to fight to keep all top growth alive
when u clone u want focus on root growth and thats why they cut fan leaves in half