Advanced Question .pos coordinates: Polar to Cartesian

[FS10inator]

According to the RecorderRef.pdf document in my Orbiter 2016 install, Cartesian is the default coordinate system of a .pos file generated after recording.

The default setting is “CARTESIAN”.

However, basically ANY .pos file I open shows the position data in the Polar coordinate system, i.e. "CRD POLAR", and the in-sim recording settings only let me change reference frames.
I couldn't find anything in the config files or setting that could point me somewhere, but I suppose someone here knows much better than I do.

EDIT: Example .pos file for reference.

STARTMJD 51983.491416
REF Earth
FRM ECLIPTIC
CRD POLAR
0.1296025 6371062.35991 -1.59295054899 0.9086632478 -4.477982429e-010 0.0001041042432 6.340581719e-007
2.0954758 6371062.35991 -1.5927458913 0.908664488455 -2.692239764e-010 0.000104104504 6.281232491e-007
6.1373216 6371085.52503 -1.59232529447 0.908667496257 15.38053003 0.0001039132544 9.371528e-007
10.1552017 6371192.30048 -1.59190811792 0.908672068222 38.28683591 0.0001036656808 1.343316209e-006
14.1589202 6371396.18833 -1.59149365492 0.908678271774 63.90971796 0.0001033846601 1.755538851e-006
18.1836259 6371708.59145 -1.5910783397 0.908686170812 91.67683195 0.0001030239067 2.1666986e-006
22.192725 6372135.08848 -1.59066609417 0.908695647635 121.4557605 0.0001026310192 2.555827136e-006
26.1999863 6372685.18923 -1.59025565385 0.908706612159 153.4106449 0.0001022099368 2.909457057e-006
30.2052123 6373364.44451 -1.58984716056 0.908718909801 185.7177371 0.0001017661907 3.224512986e-006
34.2093625 6374172.16147 -1.58944059017 0.908732390251 217.6684382 0.0001013057819 3.501961325e-006
34.388408 6374211.26096 -1.58942245371 0.908733018355 219.0891605 0.0001012848528 3.513537115e-006

Many thanks!