Hi ianp
Simple, definately not. I've found that total upgrades field the least "gotchas" than the "simple" slotting in of a new display/bit of kit.
We are in the middle of a complete glass cockpit upgrade and the thing that is giving me most grief is the new audio systems output impedance to the headset and the non standard helmet connector. A domino effect of lots of seemingly minor issues are being a real pain in the butt.
Anyway, back on thread, it can be difficult to determine if something is working intuitively as is, until someone makes a catastrophic mistake because they percieved the action they were undertaking under pressure was correct. Kegworth etc. The (un) intuitiveness of a certain control may never be fully highlighted as it doesn't have serious consequences if operated incorrectly and just becomes a pain that aircrew put up with.
The main point of the thread was to see if there were any thoughts from pilots as to why on earth certain items had been designed as they were. If they could also suggest improvements, not necessarily fully investigated/certifieable or even finacially viable, then I would be interested.
Any personal favorites from you?