A drop of 2 metres? Is it on one side of a ha-ha?
One off-the-wall suggestion. Is the width of the hedge sufficient for a
flat board, maybe 30 cm wide and a 100 long? If so, the hedge should be
strong enough to take the weight of the board and hedgetrimmer. Cut one
end of the hedge to the desired height, maybe 130 cm long, then rest the
board on top of it with the hedgetrimmer on then front of the board at
an angle with the blade just in front of the board. Keep the board flat
on top the the cut hedge, and slowly slide it along. The hedge trimmer
should then keep cutting it level at the same height .
If you think this is crazy and can't possibly work, a neighbour used to
hire a guy to cut his 4-metre tall leylandii hedge. he did this by
having the hedgetrimmer at right angles on an extension arm, and walked
along the top of the hedge (which easily took his weight) cutting just
ahead of his boots with the hedgetrimmer!
I don't think the guy had heard of elf'n'safety...
--
Jeff