Totally agree, until I've found out that it throws a Error when are not local paths:
https://github.com/apache/cordova-cli/blob/master/src/cli.js#L139

Before in createmobilespec.sh it was in the cordova-mobile-spec folder, but now the module is under cordova-mobile-spec/createmobilespec, so now it produces an exception when the local path is not found.
That's why, the project is created and then copied to the www.
Another reason is that the module is under the same folder that we are trying to copy-to, so it generates conflicts because is linking itself.

cordova-mobile-spec/createmobilespec/mobilespec <-- this is the project
Linked to cordova-mobile-spec it wouldn't work just fine.