I have a feeling that C-e should behave like C-a on a field boundary,
and leave the point unchanged when it is at the field end.  This would
make these operations idempotent.

For example, let's say the buffer contents are

	other stuff FIELD other stuff

Suppose that the characters "FIELD" have the same (front-sticky) field
property, while the rest are non-field.  Currently,
move-beginning-of-line (C-a) is a no-op when point is before F:

        other stuff <!>FIELD other stuff

I argue that either C-a should be changed to go the line beginning, or
move-end-of-line should behave symmetrically, i.e. it should have the
following fixed point:

	other stuff FIELD<!> other stuff

This could be achieved by changing `constrain-to-field'.

The various behaviours of C-a/C-e near field-field boundaries are also
somewhat surprising at the moment.

-- 
Károly