it’s because Pavlovs Dog were not British

I would agree with Song Dance till some extent.

Pavlov's Dog is a very good band, and voice of Surkamp is absolutely unique, but not for everyone's taste. I personally like it very much. It reminds me in moments about greatest female vocaliste of all times Ms. Edith Gaston (Piaf).

Yes, this band is underrated, but I don't think it would help if they were British...

I will check them out as well.  Seem to have flown under my radar all these years.

  I just went back and found Touch for some great early (1969) American prog.

I consider myself a Pavlov's Dog fan, I even wrote the Biography of them for PA (Something I would have never done if I didn't liked their music) and rated very high Pampered Menial (4 stars), but there are some questions to answer:

• Are they underrated?: Surely, they are almost unknown or hated because of the simplicity of their music (something I like very much in their specific case) and mainly because of David Surkamp's voice.
• Why are they underrated?: Because they were born 6 or 7 years too early, they played something that could be qualified as Art Rock or Neo Prog in 1974 when Prog bands were doing their most complex stuff. While Yes was creating Gates of Delirium, Genesis songs like In the Cage or ELP Karn Evil 9, Pavlov's Dog was playing Julia, Late November or Song Dance that were too simple for 1974. In the 80's or 90's they would have been a success.
• Are they Good?: Yes they are
• Are they great: No way, most of their more famous songs like Julia and Late November are nothing but poppy ballads, but of course they have excellent tracks as Preludin.
• What's their most important feature?: David Surkamp's voice, his range is simply horrendous, like a mixture between Geddy Lee and the Chipmunks, but the guy knows how to work with it. He used the same technique than Edith Piaff to make his voice tremble at the end of the phrases (Something used by French Chansoniers) creating an incredible effect.
• Is their nationality a problem?: No way, in the late 70's bands as STYX (AOR) and Kansas (100% Prog) were at their peak and both are from USA.

If it wasn't for David's voice (Something a lot of people hate), they would have only been a "C" class band with nothing really special, and probably felt into AOR.

Sadly I'm a fan, but I try not to be blinded by my taste (It's easier to be subjective and like something withoout questions or analyze, but that's not my case).