> Do people pause / resume there work in Smalltalk loading the .pr
> files or the .image files or the .st files (it does seem that the .st
> files only contain one small source listing)....

I think most Smalltalkers generally work in the same image ("workspace") for at
least a few days or weeks (maybe months or years), saving and resuming exactly
where they left off.

At some point, you may want to get a "fresh" image or an image based on the
next version of Squeak (i.e., 3.9 instead of 3.8).  The easiest way to do this
is to "export" your projects (.pr) and code (.st or .mcz) so they can be
"imported" into your new image.

I think of images are more "personal" and therefore, import/export also becomes
essential to share code and objects..