[Sephiroth]

All strategies have something analogous at least to upstream timeslots. On an uncongested upstream, you get the opportunity to inject your data; on a congested upstream, less opportunity. It's the frequency plan of the upstream and how many channels are provided under any system that matter. AFAIK, Infinity's upstream/downstream frequencies all lie in the same "band" (for want of a better term).

Also I don't think that large buffers maximises throughput except in a locality. A limiting resource somewhere else has the same effect on total round trip as at the point of buffering.

Then to address qasi's comment; TDMA is not confined to DOCSIS. So I'd still like to know what it is about DOCSIS that causes jitter.