I was not particularly talking about you. I have the impression that your approach is a very, very minor "deviation" from the "orthodox core teachings" of book 1. I also have the impression that the good folks at Davidco like to encourage people to "deviate" (adapt) if they really feel that they need to. But look at a typical project management type of person, and you will see what I mean - exactly what I wrote above: They put dates on absolutely everything that has any degree of importance. That is a huge difference. It leaves very little room for making gut decisions in the moment, making the best use of each moment, which I assume you agree is the primary way in GTD.
And because the primary way is apparently - unfortunately - so alien or unfathomable to so many, I think it can easily backfire (explode) if Davidco get too generous with their "approvals". Quite soon GTD might become seen as just yet another date-based project management approach with little or no unique character. It would then have much less value to the world (and possibly less value to Davidco, too, even financially). Who needs yet another scheduling system?
What I think David - or someone - might want to do is offer more innovative supplementary advice for those who crave a higher level of control and detail than core GTD offers. The concept of "hard landscape" would then be a good starting point, I believe. Some things simply are harder or firmer than others, even if nothing is die-hard. Booking appointments with yourself is neither innovative nor even the slightest bit "hard" nor at all in line with the more dynamic primary way of making gut-felt decisions - it is more of an "unfortunate exception" for lack of a better way to attain a sense of sufficient control, the way I see it. But to each his own. We probably all do what we want, whether we get approval or not, don't we ;-)
