Have you considered the reduction in cross-license value that this causes to the patents? Cross-licenses may be ugly, but they are much better than litigation because they allow companies to get back to actually doing productive stuff.

Most of the companies I know would be much less likely to give full weight to a portfolio burdened with this sort of agreement, simply because litigation is the stick that brings companies to the negotiating table. If one party to a proposed cross-license has preemptively given up the ability to act offensively, that makes cross-license agreements either harder to get or more expensive.

I recognize that in a negotiation, a company could use clause three to "defensively" assert against a company that is also making assertions with an eye to a cross license, but then you get into the situation I described in another comment, where you keep the legal contract but break the social one.