The early arenas fit in a single .ply on the wire. Newer captures don't. A street block at the resolution I want is tens of megabytes, and you shouldn't have to wait for all of it to start driving. Bigger scenes need a delivery protocol, not just a smaller file.

Video solved this with HLS: a manifest of segments at several bitrates, the player pulls what it can afford, the playhead never waits on bytes it doesn't need yet. SHLS v0.1 is the same shape for splats — a manifest of chunks at multiple LODs, fetched in priority order over HTTP Range. Byterange packaging collapses roughly 30× the request count: a scene arrives in three requests instead of a hundred.

The payoff is that the layers don't know about each other. The scheduler scores chunks, the loader fetches bytes, the renderer holds the last good frame. Adding a sixth heuristic later is one more scorer, not a rewrite. I kept it deliberately lean for the first couple of versions so the obvious extensions, like ADD-mode and multi-codec negotiation, have somewhere to land.