It's funny, I have never thought about NOT saving prior to check-in. My habit has always been Ctrl+7 (Iso), F (Fit), Ctrl+Q (Rebuild), Ctrl+S (Save) and then Check-In. Then this week a user new to our company tells me he's randomly losing his changes. Not understanding I ask more questions and they state...

"I have been using EPDM since 2012 and I will often make a change to a checked out part and then check it in without hitting save first. Sometimes I save, sometimes I don’t. It depends on what I’m doing at the time."

Does or did this work, checking-in without saving?  Or did their previous PDM have a setting allowing this where ours doesn't?  This is something I'm unfamiliar with.  I thought everyone saved prior to check-in!