Bitcoin Core – Want to test new releases privately on a node of your choice?

In my opinion, Bitcoin’s main vulnerability is a new release that causes problems in a way that completely destroys people’s faith in the protocol.

This means things like the 2013 update from BerkeleyDB to LevelDB. It could have had much worse results.

If each release has a 0.1% chance of causing a problem, then given enough time, some releases will eventually cause problems.

I wonder if a safer approach would be to first test new releases privately on a few select nodes (and miners) that are constantly communicating with each other. If your software is incompatible in any way, you can quickly make adjustments and switch back to your previous software. This is much more difficult to do when everyone has new software installed because there is no way to communicate with all nodes.

(We know that the software has been rigorously tested on testnet beforehand, which is good, but as the situation in 2013 shows, it is not enough.)