Domain Tasting

I read that ICANN would be reviewing the whole tasting issue wherein domainers register domains just for finding out the value via PPC ads and then delete it within the AGP. I was wondering if a such a solution was feasible:-

Maybe, ICANN can enforce a rule wherein the registrant of a domain name cannot change the name servers till he has verified the domain name(after which he cannot avail of a refund) or till the 5-day add grace period is over, whichever comes first. So, basically he starts using the domain name after 5 days or after verifying it. The registrar is allowed to put in their default name servers during this period.

The process of verification may be a bit complex as registrars would have to incorporate it into their systems but the start-using-after-add-grace can easily be implemented where a lock is placed on the name server modification.