Yes its just enough to know whats your firmware and reflashing with exact same version. You never need to know your version of CMT.

If you have flashed any wrong version like chinense CMT then its just your own fault that you made your device never to accept european CMT firmware. (you can ofcourse just flash everything but CMT and that in most cases gives you a working device).

I would still say that people are doing it blindly, and some 'resolved fixed' suggestions in this forum are just stupid. So if someone suggest that you jump off the cliff, and you blindly follow, then it's just darwinism in action.

And ofcourse there is a way to know which CMT device has, but there is no way in world that I would tell how to.