Ok, that was more clear.
What I still do not understand is why you make it editable at all.
If you want to remove the in-between markers because they are notpart
of the route registered by the GPS, then editing at all would have the
same result.

Regardless, I don't think there is a way to disable the in-between
points.
If you don't want them, then you need to implement your own editing
function, without using GPolyline.enableEditing().

You can put your own small square markers on the ends of each segment
of the polyline, make those markers draggable, and handle the marker's
'dragstart', 'drag' and 'dragend' events, and modify the line
according to their movement.
It's a bit more work, but not too much compared to what you already
have done in that page. :-)

--
Marcelo - http://maps.forum.nu
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