In fact why not disable all comments? Is the tutorial section supposed to be a discussion area or simply a place to find information? If a user has questions, then why can't he post them on the questions board?

Well, he can. But things change over time, both in the language proper, and in the people wandering around in the monastery. Even if a tutorial has been discussed in Meditations before making its way into Tutorials, single points may become obsolete after some time and/or new, better WTDI may emerge, and OTOH new people may notice something that wasn't in the first place. So, all in all, as with so many other things, there are obvious and less obvious advantages in both allowing comments and in disallowing them. But if you ask me, I'd make more or less everything commentable, including home nodes, as was once the case. (Albeit by means of a trick!)

This of course would probably require updating of the tutorials and I don't know if people would like doing that especially if the author disappears.

Actually, I've found myself repeatedly thinking that perhaps Tutorials would benefit by being more easily editable, but in the wiki sense, that is with means to also easily undo changes. However this doesn't fit well in the Everything2 scheme of things, where everything has an owner. Ideally, the two approaches are not mutually exclusive or incompatible: if there were some sort of ACL on nodes, e.g. on the basis of *NIX like permissions, then one author may allow others to edit a node of his/her own, and allow answers or not. Then some kind of nodes should have these turned on by default, and others turned off. (Should one think of this as some sort of umask?) But some nodes should have these facilities actually disabled for it wouldn't make much sense to allow one to post a question and to e.g. let him choose that everybody can edit it, and nobdy can answer it. Now that I think of it, it's not that bad a scheme in my mind, but it has the slight defect of not being implemented, and as you can see it would require seemingly unexpected complexities, so it is not likely to be implemented any time soon, if ever. So, all in all don't consider this as directly or strictly addressed to you, but rather as a meditation of mine gone wild, while thinking aloud of it. Or better: in the "typing-on-the-keyboard" equivalent of thinking aloud, of course.