How Will MetroRail's Viability Be Affected By ASA Rail?

I went looking around at information about the Austin-San Antonio Commuter Rail District, and after finding this (PDF) presentation on their website, I started thinking about how the construction of a rail line between Georgetown and San Antonio, that connected with the MetroRail Red Line at McNeil, would affect usage of the CapMetro commuter rail line.

Due to the range, and having, at least initially, to run on a moderately-heavy traffic, single-track freight railroad, the ASA line would probably use the established method of separate engine and cars. Maybe something like the MPXpress and those Bombardier double-decker cars? A definite contrast to the Stadler DMUs used by CapMetro!

But how would the establishment of the ASA rail line affect usage of the Red Line? Any commuters from Leander and Cedar Park could now travel direct to San Antonio and San Marcos, etc, as well as Round Rock and Georgetown (though rail might not show a significant advantage over car travel in the Leander-Georgetown trip, due to a much longer distance via rail). This could increase the viability of the commuter rail on the northern end of the rail line, but also eliminate part of the need for the Red Line south of McNeil, maybe, as the ASA stop at downtown Austin would actually be closer to the core office area, not the convention center, like the Red Line.

But at the same time, if you look at the people that rail is sold at attracting, the "choice commuter", who doesn't oft like to transfer (and how hard would it be to transfer at McNeil?), then this might not be relevant at all, at least for Leander?Cedar Park-Austin travel. And I have no idea how many people actually commute from Northwest Austin to San Antonio...

But if ASA RAil removed the demand for the Red Line south of McNeil, could the A&NW right of way be used as planned in the 2000 light rail plan, at least in the best possible outcome?