Originally posted by ogl I don't understand where is the focus point? The right wall of building and the lower part of road are sharper than left and central part of photo.
Perhaps there isn't one in particular; furthermore, it's a tricky shot because of the high contrast of the scene, potential foliage movement and (somehow) awkward perspective, with multiple focal planes; in addition to that, Adam has stated that it was a hand-held shot which may explain some lack of definition on the left side of the image.
While I was writing down this you have posted some photos but you have to agree that they are much less demanding in terms of focal point variation, hence the better results.
Just a side note: personally, although I don't have the lens in question, I don't find wide angle lens that good for this type of photography; people generally say that wides are good for landscape and scenery but I don't find them so adequate (only use them for close-ups, macros and occasionally architectural shots). If I need a wide perspective, I would go for a pano with a 50mm lens and stitch two or three shots in PP with much better results.