jal, I have no coder penis. I stopped coding when cobol went out of fashion .)
In your post you gave a link to some code from warsow, with a good idea (at first glance).
The problem with that idea is, that tremulous just does not have this problem with lag.
And even if you are right, that IOQ3 is not changed from Q3 in that respect, it totally bears no relevance.
Code from warsow is quake TWO, thus totally not applicable to tremulous, as tremulous is (io) quake THREE.
And that is imho the reason we have not that kind of lag you are describing.