Moiraine's comment was that she was only 'strong enough' to erase a 'few seconds', which ties the amount of power used to the length of time that it erases from the Pattern.

It is implied in many places that the magnification factor on the CK is in the region of thousands.

Assuming a linear relationship between Power used and seconds erased I think the minimum that Rand can erase using half the strength of the CK would be 10*500= 5000 seconds. That is roughly 1.5 hrs. The maximum limit would be well, well above that, but it is only the minimum tha counts here.

It is an assumption to make that it is linear, but I think a valid and sensible one. There are further problems, but I won't go into that unless you figure them out and force me to answer for them.



Aviendha and Mat are irrelevant. They weren't balefired, Rahvin was.



You say it can't be simply predicted, but it does seem a pretty neat way to explain away the proposed discrepnancy with Morgase, no? Also, Rand (with Lews Therin's memories) knows balefire much more intimately than we do and he seems to think it a valid way of testing whether Graendal has been killed or not. i.e. he thinks that the Pattern was suffiently erased to have removed Ramashalan's compulsion.