Actually it does, since its not based on the profession. Which is why the profession is called engineering, and the unit is called Tinker, and the class would also be called Tinker.
The only thing ridiculous is that you can't figure out the difference between crafting profession and a class.It's ridiculous. There are other classes in WC3 that are actually classes, not NPCs heavily relying on a profession. I have engineering and alchemy, that makes me a tinker, right? If not, then I dare you to add to a tinker something I'm not able to do now.
The highest ability that Engineers can do is make a pet and a mount. The highest ability that a Tinker class could obtain would be the ability to become mechanical, and make itself immune to bleeds, fears, and drains.
Two completely different things.
---------- Post added 2013-05-14 at 07:59 PM ----------
Because Demon Hunters are two similar to Warlocks, and Necromancers are too similar to Death Knights. Also, the Tinker and Alchemist hero is nothing like the professions.