My apologies for not commenting earlier.
I have stated that I believe the primary purpose of the planetary gearset is to maximize regenerative braking. Your proposal does that as it is a power split device able to sent power to both MG1 and MG2 in a seemless manner. It also provides an EVT in AE mode. CS mode is just one speed the way you have sketched it. However, Roosters suggestion would make it a 2 speed if req'd. Perhaps w/ a gradual engagement of Rooster's added clutch the GM engineers can make it a fairly smooth shift.
I still think the Volt is series not parallel but would like to see the connection added to improve CS mileage. my driving cycle would have me in CS mode almost 1/2 of the time. The point about Toyotas patents may also have something to do w/ it. ----and I love Herm's suggestions about all the hacking that can be done to make it so.
I definitely think your proposal here is a better one than mine that I posted in the other thread "Volt has planetary gearset."
This has been a very productive thread indeed!!!! And a great example of what Rooster coined as "group think". (with Cabdriver getting most of the credit of course.)
2012 Silver Ice Volt w/ leather and polished aluminum wheels