Concentrator!! That explains it.

I've been trying to figure out why enclosures started getting mangled (replaced by ..snip..) when I changed to Eudora beta. Turns out if you read mail in the previewer (as I invariably do) and send/reply from there, Eudora mangles enclosures unconditionally and silently, replacing enclosures with the snip rigamarole.

The inability to turn this off or otherwise control it is a serious misfeature. Why in the WORLD did they do this?

Not to mention why they call it "concentrator" in the documents and "summarize" in the services menu. Bone headed...