At various stages of a network I will cache out geo/particles etc and sometimes those stages of caching are useful as elements down the pipe for which I just resave them as alembic. I was wondering if anyone caches out straight to an alembic instead? I know its probably not best practice but curiosity got the best of me and wanted to know peoples thoughts about alembic as a caching format and how it would compare? The idea of halving the disk caching required is tantalizing.

It works, but isn't preferable, because if you have problem frames, you need to re-cache the entire thing. If you have the bgeo cached first, then you can potentially fix those problem frames, then re-cache the alembic without having to completely re-cache the bgeo sequence. You open up yourself to a world of hurt by skipping the bgeo step, but it does work.

Yeh it sounds like it is a can of worms that one doesn't want to open let alone eat.

Midasssilver
because if you have problem frames, you need to re-cache the entire thing.

This isn't the case. Alembic can be cached as a single file (default), or written per-frame. Select the ‘Render Full Range’ checkbox (also be sure to add a number pad to the output file).

There's benefits in Alembic over BGEO. The primary one for me is motion-vector data on deforming meshes being interpreted by the hair tools. BGEO as a format in this instance does not work for me (in spite of V attrs etc).

I've shifted to Alembic over BGEO and only seen positives.