I explained the situation in another post, but it has gone into revision as it contained some nasty (not very) words. This has happened to me before. A little change on the template (remove a property, for example) makes it impossible to deploy. The logs show details about alpha, the difference between models, and trying to fix it by changing the xmls normally ends up on a locked deployment task and the need to reinstall the whole development environment as BMIDE still refuses to deploy after a database and volumes restoration. I am talking about plain Teamcenter 10.1. I was so frustrated that I did not keep snapshots of the errors, sorry for that.
If you have a failed deployment, you may have modifications to the files in the %TC_DATA%\model folder, too, and the %TC_ROOT%\install\configuration.xml will also show the need to recover. The easiest way to manage your dev environment is to put it on a virtual server and take snapshots/checkpoints before deploying changes.
Siemens strongly discourages removing properties once they've been deployed. Their guidance is to just hide them.
Thank you for your suggestion and guidance. I am following the same approach here but not using virtual machines, as I am not allowed to, but backups. Deploying new templates takes me to a new level of conscience.
Have a great weekend.