I don't get it? Is it the start of a joke?
The 1800.
1600 playing Clolle-Zukertort because his or her name or that International Group is more Defineable.
Lets see.... Colle-Zukertort adds 200 points to ones rating since
it is named after 2 grandmasters. So it would be about even.
1600 playing Clolle-Zukertort against a 1800