First part is badlerdash. I've heard it a lot. Kind of a default assumption, and then
it gets spread about in the gear community when it is more about a lack of imagination
and experience with trying to get the Bass Channel to work than a limitation in the
amp/circuit.
There's so many ways to use and enjoy the versatility and options of a Bassman (Normal/
Bass/Hi/ Lo). With all of those inputs and creative routing the largest limitation is going
to be offered by the user. Just that default assumption that "it is unusable" and it needs
to be modded to be workable are notions that I will challenge every time I see them being
spread about.
Ultimately, we can do what we want with their gear. The beauty of ownership.