OK, you actually read the instructions, NOW FOLLOW THEM!!!!- Hide quoted text -

- Show quoted text -

Yes, but the instructions were written for the everyday electrician
who just goes and wires things up. I like to dig deeper and learn as
much as I can, especially if it can save me some physical labor and/or
money.

So I contacted an engineer at Jandy who was very helpful and confirmed
what I already knew - that my two valves will work on a single pole
switch, but will have that chatter in the one unit until the latter
one gets to its position. I asked if I was doing any damage, and he
said that the only problem (and the reason they say not to do this in
the manual), is that the motor can overheat if the valves are run for
a long time. Since mine travel 45 and 90 degrees (about 10 seconds)
and are operated about twice per week, he thought there would be no
problems.

So problem solved - I had no real problem to begin with, and now I
don't need to crawl in the attic space and add additional wire runs,
double pole switch, etc.