Multiple storeio types?

I just wanted to check with someone who understands storeio better than
I do...

Is it expected behavior for only one storeio module to work at any given
time? I.e. if I have one directory configured with ufs and one with
aufs, should the ufs directory not work?

I see nothing in the docs (and nothing in the source that I can figure
out) that indicates this is the case, but the actual behavior I'm seeing
says it is.

Thoughts? (My reason for asking is that I'm fiddling with using a RAM
disk for small objects to ease the write burden on the disk a bit using
max-size for the RAM cache_dir, but I'd like to not use aufs as it is
just needless process and memory overhead since blocking should not be
an issue. It works fine with aufs alongside the other dirs, or with ufs
when the other directories are disabled.)

Thanks! (BTW-Using HEAD from two days ago, if it matters.)

-- 
Joe Cooper <joe@swelltech.com>
http://www.swelltech.com
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