Not to be a party pooper, but I'd like to ask for a more focused approach here in these review threads.
What are needed are -- roughly in order of priority:
1) Succinctly stated objections to the constructs as they stand.
2) Succinctly stated objections to proposed revisions.
3) Succinctly stated minor revisions.
While major revisions and additions are as such fine as well, to get through the review during this millennium it is more important to focus on throwing out things on which there isn't a clear consensus, and less important trying to perfect things that people have different ideas about.
Based on the input so far it seems to me that there is no clear current or historical consensus on how exactly SWITCH &co should work, and unless a clearly superior interface suggestion appears, I will remove them from Alexandria in a week or so, moving them to another package -- call it BYZANTIUM.
(In case there are people reading this who are not clear on it, Alexandria's purpose is not to implement every CL utility under the sun -- though it may feel like it! -- but rather implement those on whose behaviour there is a reasonable cultural consensus.)
Cheers,
-- Nikodemus