There is a doctrine in patent law called the "doctrine of equivalents." [1] In short, it limits the ways you can use obvious work-arounds. In practice, it's very complex because there are often good reasons why they specified an "incrementing" counter rather than "any counter," but the idea is that you can't make a trivial change to get around the bulk of a patent.*

[1] http://en.wikipedia.org/wiki/Doctrine_of_equivalents

* I am not your lawyer, get a lawyer, etc.

If the "obvious" in "obvious work-arounds" matches the "obvious" used to determine patentability in the first place, we're safe.

Semantics. Are you decrementing the counter by a positive number, or incrementing it by a negative number?

Yeah that's the point. Sometimes semantics distinctions matter to the law. So can you just decrement by a negative number to get around it, legally?

Semantics especially matter in patents. There is a famous historical case where a patent specified a horizontal beam - since you can never have a perfect horizontal beam in a real machine everyone was free to break it.

It's why every second word in a patent is "substantially"

I would interpret the 'increment' in the claim to mean increase (by a positive amount). The proposed workaround would start at the end and decrease the counter.

Any workaround would help going forward but there's still the issue of past infringement. Invalidating the patents fixes both those problems.