To Kevin Randall's questions--yes, I'd be happier if we had a controlled form of the work/expression entry in all cases in addition to the form found in 1XX/245. I like Bob Maxwell's suggestion that all work/expression access points be managed as well-designated added entries. Getting systems to create access points from the combination of 1XX/240 has been too much of a struggle, whereas they handle 7XXs pretty well. Since there's no coding to support distinguishing a work/expression title from a transcribed manifestation title in 245 $a/n/p, there's no way a computer can select from 245s only those titles that should be indexed at the work/expression level.
Ultimately we'll want a separate description for the work or expression which could be linked to the added entry structure in the manifestation description. That would provide more complete information about works/expressions than our records currently do, more flexible control over the text form of these access points, and ideally provide it a shared space so that the work of describing the work/expression would only need to be done once (per set of cataloging conventions) and would not need to be duplicated (e.g., think subject access) when describing each manifestation.
As for getting rid of 1XXs--the 1XX is doing several things. In addition to generating a name access point, it is also used by some applications to harvest citation data specific to the manifestation. We'd need to account for that somehow, or accept that our 1XX-less records are poor sources for harvesting citation data (not that they're ideal sources now by any means).
I was asked privately if separate work/expression/manifestion access points are needed for discovery. Discovery is a many splendored thing. When I'm examining the extent of a library's holdings for a prolific author or major composer, having good, designated work level access under the creator name can simplify the review of a result set significantly. The works can be listed in a compressed index and decompressed to show more detail about a particular work's expressions and manifestations. Programming conditional behaviors that would take the user directly to the manifestation layer when the holdings are scarce would save that user's time without wasting my time wading through lots of irrelevant manifestation data when I'm doing a more comprehensive review of extensive holdings or looking for the holdings for a particular work found in multiple manifestations.