Yet they still don't train TSOs to recognize marijuana, so what is the purpose? Can the TSA hold the marijuana like they hold liquids and small knives?

I wonder what will happen if the Federal Government formally agrees not to enforce federal law in those jurisdictions in which state law permits possession? For example, what would happen on my flight from DRO-DEN this month currently and if federal law is no longer formally enforced in the future if another passenger is found in possession of marijuana.