Outline of "traveler-kinematics"P. Fraundorf (2012) "A traveler-centered intro to kinematics", arxiv:1206.2877 . in a Schwarzschild shell-frame, where we've put the geometric acceleration (GM/r2) on the left side of the equation with sum of proper-forces over mass (ΣFo/m ≡ α). This is done because we usually think of shell-frame gravity as a radially-inward force or geometric-acceleration, much as we usually think of accelerated-frame centrifugal-force as a radially-outward inertial-force or geometric-acceleration.