Shouldn't Aviendha be back by now? I am not sure how far the timeline can be trusted, but it she must have been away for at least 2 weeks (20+ days) by now.

I know that she had to spend 4-6 days to travel to Rhuidean and that she might have spent several days in the Ter'angreal as well, but it still does not add up. Plus, shouldn't Rand have wondered what was up with her?

Wow, that's a clever question. Looks quite unlikely that none of the sisters taken had a warder left behind indeed.

Of course, there are several reasons why it may not work:

1) Warders are not very likely to be left behind. If they are there, they probably die before letting their sister be taken.

2) Those with their sisters taken are not likely to stay in the tower. Warders don't tend to think (too much) when their lady is taken, they follow.

3) Everyone forgot about it (well, Egwene, at least), then it was too late.

4) Maybe it's not so easy to take those to'raken off the sky when they don't fly low.

5) More likely for warderless sisters to be taken.

6) A limited number of sisters were taken at all.

7) Too scared to try and take them back? By the way, they can't use the power as weapon.

Siuan Sanche can see Ta'veren.

I pronounce Elayne as 'eye-lene' yea I know that's funny but I like it better that way.