If I'm not mistaken, the conclusions from posts in this thread are:
3. there are methods (like cryptographic "random" sequence), which
guarantee no conflicts. So one should resort to that.
Some web research suggests that random sequences are not great for indexes because of the resultant "keyspace fragmentation". I'm assuming that means a low number of nodes in the btree leafs, so an increase in memory usage for the index?
Just a thought.
Geoff