Charles On this topic - sometimes one can think of a framework as 50% territory - only half made. On the other hand a number of common formations (I'm thinking of those based on stones on the fourth line, in particular) are better counted as closer to the apparent score. Perhaps at 80% or more of what is sketched out. That's because a deep invasion upsets the balance of influence, and so doesn't subtract as much, in net terms. This anyway is my experience from games.
Bob McGuigan: I think moyo invasions usually end up in gote, which seems interesting considering what Bill said on the main page. On the other hand, erasure is usually sente. And there is the issue of timing. We are advised that the right time to invade is just before the moyo becomes territory. If the timing is right that should make the invasion worth more.