Hate to dfiffer here...
Why do you need a DI unless required by the ANO as a PPL??? Cant you fly with just a compass?
As an instructor I dont need a DI for Effects of controls pt1 or part 2, nor ex10A, 11A, 10B.1, 10B.2 - none of these require use of the DI per se - my students arent navigating at this stage and therefore navigation of the aircraft is controlled by me and they fly by reference to visual points outside the cockpit - which is where I want them to be flying - not heads inside.....
So it can work quite happily - you just need to be intelligent about how you use an aircraft.
P.S Microlights manage without DIs. This may come as a shock to some....In fact I even got my PPL without ever seeing a DI.....
Regards,
FF
IO540-C4D5D - With regard to 'sad commentry on GA' - I assume you are on an airfield where approved engineers are available 24x7. Ah thought not. !!!! happens as they say....it takes time and timing to get problems rectified.
FF