Even in a G-103 you can steepen the approach by increasing airspeed with
full
spoilers. The drag increases with the square of the airspeed.

Mind you it takes a bit of time in ground effect to get rid of the airspeed
in
something with puny spoilers. But any headwind helps with the groundspeed.


The AAIB report does not discuss whether windshear might have overpowered
the ailerons or whether Matt attempted to decrease the bank.

At a 60° bank there's some 42' of height difference between the wingtips.
In
active air, that's lots of room for a shear. Landing straight ahead in such

conditions would limit the chances of getting into a bank you can't get out
of.