. . . apologies if these are obvious or inherent conflicts that you can't do any think about or don't intend to.

With drupal caching turned on subedit just pulls the whole node edit form into the popup.
Which allows editing and saving followed by the errors described in my earlier posts. . .

I can't remembering what was going on with Global Redirect / Pathauto but I got to a point where I was pretty sure they were conflicting with subedit.
Got rid of them.

Now subedit works again but with the same "Bad response form submission" confirmation dialogue.
Again refreshing the node page shows the edit has held but I don't get the default drupal confirmation message, which indicates to me that the full process isn't working harmoniuosly. . .