Run this by me again. I don't understand the whole "transfer excess momentum" business. How would this be done? Why would this be important?
Using the poodle example, my guess is that the transporter:
1. Dematerializes the poodle from matter into energy (or phased matter, depending on your series). The momentum of the poodle is preserved.
2. The poodle is now in the transporter buffer.
3. The process is reversed and the poodle is re-materialized.
During the time between step 1 and 3, the ship is in orbit over the planet and could've had a miniscule fluctuation. So, even though you're beaming back to the exact same pad, the ship might've accelerated or decelerated by a tiny amount. That amount could mean the difference between putting the matter back together slightly out of alignment or bumping off the pad or even ending up at a slightly different orbital velocity relative to the planet. On a larger scale, like beaming down to a planet or another ship, the transporter would need to ensure that the materialized person or object will have the same velocity as the environment they are beaming into. This would be fiddling with potential and kinetic energy values while in energy state to probably avoid ripping a person apart if being applied in the matter state. At least that's how I see it