Such a change could necessarily prevent the duplication of tracks which harms the playing experience, especially on survival servers.

Sorry? I'm afraid I don't understand the issue.

I always thought pushing tracks enabled some interesting things.

There are occasional duplication bugs relating to pistons, rails, and I think slime blocks, so he wants you to disable pushing them with pistons to "fix" it.

To many interesting vanilla train mechanics use this feature. It is not RailCrafts job to fix vanilla minecraft dupes.

But if you try to push such tracks from railcraft, you will find that you cannot push them-tested in rc 9.12.2.0.

That will no longer be true in 1.10.2, all of the Flex track variants will be pushable (no tile entities).