Does the dynamic publish policy generation scale?

First of all, thank you for the tutorial; it has been extremely helpful. I wonder, though, whether or not creating a new policy for each user would scale. Are these policies temporary? Reading the IAM documentation, I found that you are limited to 1500 policies per AWS account, and it doesn't seem that, if each user has a policy, this solution would work for over 1500 users. If it would not, is there an equivalent, scalable way to do this? I have a very similar use case.