'Edit Vertices' not taking effect

[JohnNiles]

This is a seemingly simple problem that has become a huge, mysterious problem

I have a line that I want to change the geometry of:
[ATTACH=CONFIG]13191[/ATTACH]

I select the line segment, then 'Edit Vertices', then the particular vertices I want to change and then change their position:
[ATTACH=CONFIG]13192[/ATTACH]

I then click "Finish Sketch" and the line reverts back to the original geometry:
[ATTACH=CONFIG]13193[/ATTACH]

If I select the segment again, and again click 'Edit Vertices', the updated line will suddenly appear and will be the only segment that can be edited (not the original):
[ATTACH=CONFIG]13194[/ATTACH]

I can't make heads or tails of what is going on, and this has basically stopped any further progress on this particular task. Any clues about what might be happening? Thanks!

[LisaStanners]

A couple questions that might help me to reproduce. Can reproduce this with any data? Do you move multiple vertices at the same time? Do you drag to change the position of the vertices? Do you ever double click to start the edit vertices mode? or to finish the sketch?

Thanks,
Lisa

[Anonymous User]

Original User: jniles

This has cropped up again and again since I posted this.. it's such a complete mystery and such a headache that I'm very close to closing ArcMap for good on this project and just doing everything in Illustrator.

Here's an egregious example of how messed up things are:

1. A polygon that I have attempted to cut is selected using the Attribute Table. It shows all the vertices.
[ATTACH=CONFIG]15330[/ATTACH]

2. I select Edit Vertices and it displays the vertices that can be edited. What about the vertices that are selected but not editable?! Where do these exist? Do they exist? I can't trace to them, select them, or edit them, but they show up when I select the polygon using the attribute table, and they are displayed. WHAT IS GOING ON?
[ATTACH=CONFIG]15331[/ATTACH]

This is mindbogglingly frustrating.