I have no idea whether the following is practical, and/or makes sense regarding d-i's logic, etc., but I'm wondering whether it would be possible to have checking "Debian Pure Blends" activate a follow-up screen which would list all Blends. This way, we would get the previous tasksel screen back, and only present the Blends to users who're actually asking for it. And that, without changing anything in debconf, its (non-)support for structure prompts, etc. Merging two tasks lists obtained in two stages shouldn't be too hard, I suppose. But does that make sense? Again, Christian is more knowledgeable in this area, and might have more insight.
I tried to read the whole thread and then I'll summarize my thoughts.At first, I'm not happy with the idea of Pure Blends tasks mixing up with standard tasks. I fully respect the work done by the variou sblends teams, but having our usual longstanding "standard" tasks kinda lost in the middle of "strange" and obscure tasks which the average user has no idea about what they're about...is a no-no for me.
I still remember Joey's objections about *not* having users forced to choose between desktop environments....because, contrary to what the average geek thinks, most people have no idea about what is a desktop environment. So, just imagine if we present them with "Hamradio", "NeuroDebian", "Debian Med" and such a list of unsorted strange things.
Not to mention that most of these tasks titles wouldn't be translated, while other tasks are.
So, yes, I'd object strongly to mixing up Blends tasks with other tasks.I think that the idea of blends choice in the boot menu has already ruled out for several reasons, so I won't develop here, but just add one more reason : this is untranslatable.
That leaves us with the idea of a "Debian Blends" choice in the standard task menu, which would lead to a dedicated "blends" menu. I think this is the best compromise to do, provided we find a good name for the menu entry : "Debian Blends" or "Debian pure Blends" is a great name for the project in its entirety...but probably not for the menu entry. Again, because it means nothing to Joe User.
So, with something like "Special-purpose packages" or "Specialized installations" or whatever along those lines, *then* a menu with the Blends list (unsorted) and the possibility of going back just in case people see the list and think "heck, I have no idea about what this stuff is about"....then I'd say this is the way to go.