The post only says that TextSecure have begun implementing this. The hash-parent-pointers is a good start and enables more functionality in this direction, but it doesn't mention other strategies that actually ensure the user's confidence in consistency. For example, checking for others' acknowledgements, heartbeats, or resending a potentially-inconsistent situation. None of this is that hard, but the post is missing important chunks, yet you are waving this over.

I will also say that whoever has been down-voting all of Nadim's votes (and it seems there's multiple people) ought to be ashamed of themselves. This is ridiculous.