Why doesn't the ODB Editor functionality work on OS X 10.7.x?

MultiMarkdown Composer 2.4 added support for the ODB Editor protocol. However, it appears that this code causes an error on OS X 10.7, despite working properly on 10.8.

As some of you may remember, trying to include support for the ODB Editor suite in the original version of MultiMarkdown Composer lead to some issues with 10.7 despite working on 10.6.

In the personal opinion of Fletcher Penney, the ODB Editor protocol is a bit outdated, and seems unnecessarily difficult to implement. Additionally, Apple's sandboxing requirements and the need for temporary exceptions to allow ODB Editing to work imply that it will not continue to work indefinitely. His efforts to collaborate on creating an updated protocol with the developers of QuickCursor and MarsEdit (seemingly the primary software still used by OS X users that rely on ODB Editing) have not lead anywhere.

For the moment, the ODB Editor protocol works on OS X 10.8. It doesn't work on 10.7. It is not clear yet whether it will work on 10.9, but preliminary tests suggest it might. But at any time, Apple could change the rules regarding Apple events and sandboxing, which could break ODB support.