There is mention in that other thread about "banking" the feeds, that it is running the shade motors in parallel so you simply have one AC wire jumping from window to window. That is not a good idea.
Manufacturers warn that there is a feedback from one motor to another that can cause issues.
There may be a device available for some motors that you can purchase extra to aid with the situation, but why ask for trouble. My advice is to not lock yourself into a situation where you are running motors in parallel.