We should also remember that it is not just PFO where we can have 'problems, as per my post about low flying in RAFG. ANY airport where the air is hazy and you go from down to up sun can catch the unwary. Having an approach aid (which SHOULD be SOP) to back up the 'visual' is vital and a quick shufti over the shoulder when downwind, back towards the field, before a final decision is made is a very good idea.