One key to their matches is when they are pinned in the forehand corner and have to reply to a hard shot. Serena will hit a running forehand crosscourt offensively and sometimes Venus will loop it down the line or net a forehand crosscourt. She *must* develop an anwer to this. Serena goes to this play like money in the bank. Venus must have a better reply when she is pinned in her forehand corner. But I do expect one of them to lose before one of these finals. I don't think Venus and Serena will both get to all finals of: Paris, Miami, London and NYC. It is just too much to ask.
BTW, Anton, Venus' forehand deserted her that is why she started playing it a bit safe. it just another area that needs practise or perhaps revamping.
but as she implied in her interview now that it has contributed to costing her the AO, hopefully she will work on it.