Richard,
I may lighten the very corner of the wall. The darkness was caused by:
1. Being in a shadow.
2. My using a 2 stop hard edged ND grad brought down to stop the sun burning out.
I also used a 2.5 stop soft edged ND grad but it's effect is difficult to see.
On a similar point I like light and shade and find the present fashion of lifting shadows or, in my opinion worse still, using HDR to lift shadows to put detail everywhere and destroy any natural look in the image. This is not to say that this is a SOOC shot, far from it and I have lifted shadows otherwise much of the hillside on the right would be much darker and the wall itself on the face looking at you would be very dark if not almost black.
Anyway, thankfully we are all different and see things differently.
Ken