The "Uncle mining" currently tested on Masari, a Monero code-fork seems to correspond to your description. As far as I can tell, reducing theThe block time is not planned by the Masari teamto be reduced to 60s. This test will allow to see if there are any reasons not to implement this concept.
You can see the current state of the implementation in this pull request: https://github.com/masari-project/masari/pull/71.