My bad; I've been using about double the visible diameter of the moon. Looking up the moon's visible diameter at NASA I get "Apparent diameter (seconds of arc) 1896 ...". So double that to get 3792 - which is about ONE degree. Sorry.

I saw a Foucault's Pendulum at a science museum in Paris (not on a pole) and it was going around the circumference once a day. Not sure how they managed to power it w/o interfering with its action. There were little cones around the circle that the pendulum would knock down. Saw another one at the Boson Museum of Science. No cones but something like sand it was making a track in. Still no idea what input was making up for friction.

As far as how I use a guide laser... I clip a guide laser to the tracker (laser and tracker motor-center are parallel). Find Polaris (using side of Big Dipper so I know I'm looking at the right star). Find Kochab (part of Little Dipper). Draw an imaginary line between the two, point laser at a point on that line about 2 moon diameters away from Polaris. Not perfect, but close enough for the long exposures I take. I typically use a wide angle (14mm on a FF) but sometimes as long as 300mm. My tiny tracker hasn't got the torque for a longer lens - and no way to mount counterweights. I live in an area with a lot of light pollution so light/portable was up there with "not expensive" when I was picking one out.

Guess I'll go correct the comment in case it messes somebody up...