Hi Overrun,
I am not sure about the gradients being non-compliant, since departures regularly use the full lenght distance (2800m) when departing on 29. However, I am sure the fact that the 29 threshold is at the bottom of the slope worsens the obstacle situation for approaches on 29 and departures on 11, and I believe this is the main reason for the threshold displacement for approaches on 29 and why on 11 the TORA and TODA are limited to 2300m (clearly obstacles not such a big issue for ASDA
)
Also I believe the ASDA for 11 is less than 2800 because the remaining distance is a RESA (can't get the RESA further out east because of the mound which acts as blast protection).