Here's what I don't get...
Where does it say there can only be one PSK QSO per channel?
The only thing I see is a limitation on the bandwidth used per channel.
I think the OP believes that hams cannot act like hams and follow rules.
There is only one group of radio users that when mandated to use channels disrespect the rules and we know who they are.
I would like to believe hams can toe the line and respect the regulations. There is a future in sharing the commercial and government HF bands We could in time end up sharing a good part of the HF spectrum with our fellow radio operators if we don't blow this....