Understood, which is why I said

I don't think bag matching will have as large of an impact on carry on's as requiring them all to be checked.

If all they did was bag matching then it's not a huge deal at all. If however they are searching the bags as is generally expected to happen starting Friday, and they don't have the equipment to x-ray or do it any other way then opening each bag then it will affect carry on's, there will be many more of them and they will be as big as the airlines allow.

But I completly agree with you, bag matching alone will have no effect on carry on's at all.