Tracking forward/backward camera motion Has anyone been able to track camera motion going primarily forwards or backwards?  It seems that whenever I try, Blender is unable to make any sense out of all the trackers going in all directions and gives me a crazy blue error line in the tracking graph editor and triple-digit solve error values, despite all the individual trackers having solve errors under 1; I've tracked many primarily side-to-side shots over the years, so I know how to do a good camera solve.
I'm just wondering if Blender's 3D tracker has no way of interpreting forward/backward motion, which sounds like a crazy idea, given that Blender is so good and that no one seems to have noticed such a huge chunk of tracking functionality to be missing; but at this point, after having failed to solve multiple such shots over the years (and actually seen no examples of other people doing it), I'm really starting to wonder.
If anyone can say that they have successfully done it, then I'll have my answer (namely, that it's not a weakness in Blender, but something I'm still not doing right, which I can maybe try getting some help on in another post).
EDIT:
Attached are the blend files for a couple of the shots I've attempted tracking over the years (that I've been able to find).
https://drive.google.com/file/d/1P4EOqos0YEDJkJnqh_Xsa4CcL2eU_XSY/view?usp=sharing
https://drive.google.com/file/d/1DZ0nhQDz_Nh0fraI2oXzY7AzF5u9TNIO/view?usp=sharing
Blender can track backwards and forward accurately with no problem. I've done it many times.
So there is your answer.
Most likely the issue is with the compression used on the video. Intraframe compression or image sequences works great. Video with long GOP does not and might lead to errors retrieving frames going backwards.