Here's a little bit of an update, with a Wile E Coyote solution to turn this into a very competent astro mount:
One of the first issues with using this cinema tripod and head is that the head is designed for -45 degrees to +45. I needed a range of 0 to 90, so I took a used TeleVue Upswing head I had purchased from a CN user, and then I mounted it to the large 6x9" top plate of the Hercules head. I then added an off center ADM saddle to the Upswing cradle and tilted it back 45 degrees, resting it on the back ledge to provide me with the usable range. I could secure and lock the cradle with the Upswing's brass fasteners, which is working rather well, provisionally, but there is a better solution to locking the cradle at 45 degrees relative to the Hercules top plate.
I will soon add a 1/4" heim joint to make a solid 45 degree connection between the ADM saddle and the Hercules top plate, running the bolt through the pre-existing registration channel on the bottom. This should provide for a very solid mounting and will cost less than having a fabricator machine a 45 degree wedge. On the other hand, the nice thing about using this Upswing cradle to lock the setup at 45 degrees is that if I loosen the brass fasteners, I can evaluate the scope's balance relative to the cradle, but it is not necessarily balanced to the axis of the head's tilt.
This modified tripod and head is proving itself to be very fun to use for astronomy, where the large geared pan and tilt cranks allow me to track very smoothly and with high precision at magnifications of 300X and up. I was able to easily keep a target centered in the field of view by using the geared cranks like oversized dial knobs-- tracking was so good that my narrow 50 degree eyepieces at over 300x magnification still felt like I had an enormous field of view on tap, where I wasn't worried about my target drifting away at all, since i could easily keep the image steady and centered.
The only faults with this setup right now are the relative weight and the heavy duty spring loaded mechanism for controlling tilt. The head is rated for 50lbs, so my fully loaded 25lb scope can be handled just fine... but if my balance isn't correct and I do fast adjustments to tilt, the OTA will spring back and forth unless I add a light touch to dampen the induced vibration. If I make slow adjustments to tilt, as I would for tracking, there are no vibrations. The center column, fully elevated, doesn't add too much vibration.
I definitely recommend this tripod and head to other CN'ers interested in alternative mounts with slow motion controls and alt-az configurations ... if it can be found at a reasonable price. It's probably the closest I have to a pier mount, without needing to commit to a pier in a fixed location.