The Paramour/Stereomour has always been cap coupled.
The 300B Paramount has also always been cap coupled.
The 2A3 Paramount was directly coupled, and it required some monitoring of the driver plate voltage and adjustment to keep the 2A3 optimally biased. A convenient way to run a 2A3 when you have more B+ than the tube would like is to use direct coupling.
We have never produced a directly coupled 300B amp, as the voltages become very high (600+V of B+).