The weakness of the GPL's patent protection was one of the reasons for the move to v3. I think that you're vastly overestimating the 'implicit' protection that the GPL provides, which to my knowledge has never been tested in court. Even the FSF states this in their FAQ on v3:

In many countries, distributing software under GPLv2 provides recipients with an implicit patent license to exercise their rights under the GPL.

http://www.gnu.org/licenses/gpl-faq.html#v2OrLaterPatentLice...

Many countries, but not all... and it's not clear in the case of v2.

> The weakness of the GPL's patent protection was one of the reasons for the move to v3

I agree that v3 is more clear about patents than v2, but it's unfair to call a protection that was never used (possibly because it has been a successful deterrent) "weak". It can only be weak if it doesn't protect. So far, it has been effective.

I think the wording in v2 is clear enough. One cannot impose any additional restriction and cannot force fees on users and re-distributors. That protects not only against patents but from anything that looks like one.