When I first posted on the PSX, I kept using the term "age difference" as meaning something other than the term "reciprocal time dilation". It turns out that age difference here means the coordinate time difference between where a perspective's line of simultaneity intersects the two velocity lines. Basically, it means the same as reciprocal time dilation.
So at .6c if Bob's line of stationary simultaneity intersects his velocity at t=4 and Alice's at t'=3.2, the age difference is 4-3.2=.8.
But from the Loedel reference frame, which is defined on wiki as the frame of reference in which two collinear velocities become equal speeds in opposite directions, the Loedel velocity of 1/3c lends a perspective and Loedel lines of simultaneity where the Loedel age difference is 4-4=0 according to this Md:
The Loedel reference frame's lines of simultaneity join coordinate times that match the time labels of proper time. In conjunction with this question here, the Loedel age difference gives a picture of how age difference progresses for proper time coordinate labels (but not proper time itself as that is invariant of perspective more info why here).
So my question is whether "Loedel age difference" can be used as a valid term distinct from the term "age difference" used here?