I thought it was pretty obvious why she hasn't been around (apart from sick child)
for this latest release NO have gone 'professional'. either because they have been told to by record co or now they have one eye on retirement (either through old age or lack of sales). dont forget they did not make a lot of money during their most creative periods (ok so they did but poured it down the hacienda)
So everybody gets on the promotional treadmill (though i reckon hooky loves it)
Then, if you are going to fill stadiums and sell lots of live dvds the thing to do is to loose the variable level of performance that NO is ahem, renowned for.
Say goodbye to experimentation. Say goodbye to setlists that change. Say goodbye to (a lot of) chance.
Say hello to tapes. You could see it coming on the 3:16 dvd. nice big button above Gillian's kb to kick it off. If you saw the article on NO when the acid loop competition was running you saw a reference to a guy producing the live sound. looking at his article you saw him talking about taking stuff off tapes (and even taking stuff from LWTUA, and the carbon flies off and they have to have the tape baked). 511 is just a trawl through the orignal tapes of many songs with barney going 'whoooo!' every 30 seconds to show its live.
So in effect you make Gillian redudant in the live arena as you are after the 'just like the album' sound.
New album is very guitarry. OK lets get a guitarist in. Whoa! even better. Now you have an extra guitarist you could possibly now play some JD songs, as Barney cannot sing whilst playing (which is one of the main reasons they don't tend to play that stuff too much previously)
Now maybe... maybe... maybe if we fill half the set with JD tunes you can convince some of the audience to buy some old JD stuff and shift some more gear for the retirement fund.
You have to realise, they have totally sold out, which isnt surprising as they are getting older and need some financial security.
I don't care about that as long as they continue to write good tunes. but i wont be seeing them 'live' again.