WOW! Thanks Tom.
One other instance I found... and didn't see is equation curves. I noticed in making involute curves that the beginning angle was huge where you expect a perpendicular. I found you had to change accuracy significantly to dial this down, but never got to zero.
When you work with milliradians and microns on a regular basis, these little things get to you very quickly.
I will have to put the accuracy_lower_bound in my config.pro files for those clients where this is relevant.
There should be a lot more automation built in with intelligent notices of what Creo "is about to do" when you make a feature that could affect accuracy. This should be a guided process rather than a trial and error process. For instance, a merge of a large and small part can throw up a warning stating that the accuracy of the large part will be changed to match the small part. A failed feature should ask if it is okay for Creo to test the failure at different accuracy levels... now that would be an upgrade in functionality; and probably what we would expect in the specification! You can accept the value change to create the feature and go on about your business.
Day 2 of my Creo experience was modeling a silkscreen onto a piece of sheetmetal. A 19" panel with a .0015" extrude just doesn't work by default. I had NO CLUE why this didn't work. And yes, I expected Creo to give me useful advice instead of the generic failed feature notice. I saw nothing to guide me to accuracy. not at that early stage of my reintroduction to Pro|E.