[santacluster]

That just means you haven't properly aligned your developers' interests with your business interest.

Limiting developers in which languages and technologies they can use is not going to solve that problem, it merely addresses the symptom. Developers make hundreds of little less obvious and visible decisions that have a long term impact on your business. Picking the tools should always remain a developer decision.

If you a) hire the right people and b) make sure your goals are aligned, your developers limit themselves to a few core technologies. If not, you're screwed anyway.

(And yes, that does mean mutually accepting and respecting the fact that your developers' interests in exploring new things and your business interests in may not be aligned indefinitely.)