So Lleyton is still vulnerable going into IW...
Quite, actually. At first glance I thought that this would make a huge impact on Andre's chance at number one, but really it doesn't.
Hewitt defends 220 MORE points than Andre does in Indian Wells and Miami. The Scotsdale winner only gets 175 points. So even if he wins Scotsdale, he still has to gain more points than Andre in Indian Wells and Miami (combined) in order to be number on when they are both over.
Now, dealing with just the period between Indian Wells and Miami:
Hewitt's worst optional event in the last year that is being counted, is 's-Hertogenbosch, where he won 40 points. So if he wins Scotsdale, he'll gain 135 points (175-40). Which means that with his Indian Wells points off, he'll have 4115 points (4480-500+135).
Agassi with his Indian wells points off, still has 4345 points, and a 230 point lead on Hewitt with their Indian Wells points drops.
This means, that for Hewitt to be number one right after Indian Wells:
IF he wins Scotsdale, Hewitt has to make the finals and hope that Agassi loses in the round of 16 and earlier. Otherwise, he has to defend his title, and hope that Agassi loses before the finals.
If Hewitt doesn't win Scotsdale, it gets a little bit easier for Agassi.
Basically, if Hewitt doesn't win Indian Wells, odds are heavily against him. Especially seeing as Enqvist just did Andre a bit favour by knocking him out early...