This caused a near miss the other day, and I thought I'd share it as I haven't worked out a solution yet.
In L3 on the 5 lane section of the M25, and I need to move over into L2 as the M3 interchange is coming up. What happened next was along the lines of mirrors... signal... mano

-where the hell did he come from? Actually since the cab (an MPV) doesn't have wonderful visibility from the door mirrors I do an over the shoulder check before changing lanes, but on this occasion I managed to miss a small car undertaking me in both the door and rear view mirrors, and most worringly failed to see him when I checked over my shoulder. I believe this was due to my eye height, the other vehicle's low roof line and the head rest on the near side centre row seat blocking the view through the 3rd side window. I think this was one of those situations where he moved from one blind spot to another in such a way that I was always looking in the wrong place. I'm pretty confident that had this been at night I'd have seen his head light beams on the tarmac moving towards me, but in the daylight this could easily happen again.
I think the sequence was as follows:
Rear view mirror - other car hidden by D pillar
Look over the shoulder - hidden by headrest
Door mirror - in mirror blind spot
Signal
Begin to move and happen to look through passenger door to see him alongside.
Any suggestions for me? I think I should probably change the order of my observations, but to what? Rear view, door mirror, over shoulder? Door mirror, over shoulder, rear view? Or should I just put a sign on the back saying "Sh

visibility - please don't undertake"?
