> * me not understanding how Seaside / Squeaksource protect against
> concurrent modifications internally

Seaside serializes requests for a single session. It does not
serialize requests among multiple sessions.

> * the singular use of a single critical section for saves only (!)

I don't remember exactly what SqueakSource is doing. I don't have an
image accessible right here, but maybe Philippe can comment on that?

> * the priority of the save being lower than normal which ensures that
> (unless there are other means of synchronization that I am not aware of)
> any request that comes in during the save *will* concurrently modify the
> repository being written.

I see, you are using the reference-stream serialization.
www.squeaksource.com had to drop that approach after a few months,
because it got far too slow (today it takes minutes to serialize the
whole model). As I said, we are just saving the image.

Lukas

-- 
Lukas Renggli
http://www.lukas-renggli.ch