I use a custom :Drop command (that does some more magic), and use that almost exclusively to open files in Vim. Effectively, an :edit / :split command is issued under a try..catch block to catch and gracefully report any errors that occur during file open. Unfortunately, the try..catch changes the semantics inside s:CheckRecover(). When the :recover there fails with an E305, instead of continuing with the diff-split, the execution is aborted, and the plugin doesn't work for me.
The fix is to add a try..catch around :recover. It keeps the verbose recovery messages visible, so that there is still an indication when recovery failed.