Microsoft argument against a ATSC 3.0 simulcast station is unworkable in some situations.
Let's take Syracuse, NY. The major stations are:
14 FOX
17 ABC
18 CBS
19 NBC
20 PBS
If anyone on channels 17-20 wanted to switch to ATSC S 3.0, they could do so.
BUT as soon as they constructed a SFN on their own channel from another location that transmitter would interfere with the stations on channel one above and one below.
In this case the Microsoft argument fails.