Confusing Tone Pot sweep(Jazz Wiring)

AFAIK... best results for Jazz bass pots are linear volumes and audio taper (log) tone pot, this is supoused to give a nice volume sweep when playing clean uncompressed sounds and a usefull tone range.

Last night I re-did the wiring on a jazz bass, I tried a 500k pot in volume position, it was supoused to be an audio taper pot as described by the ebay seller as I later checked, to find out that most of the volume was in the final 8-10 turn instead of evenly distributed.

"OK, dumb me, this is an audio/log volume pot" so it's uneven in volume, let's use it for the tone pot. But to my surprise, when wired as a tone pot most of the highs reduction happens in the first 0-2 range!!

What's going on?
A suppoused audio/log pot gives uneven volume (volume jump from 8 to 10) AND uneven tone (Brightness jump, from 0-2 it works, but from 2 to 10 it does little or nothing for the tone sweep)

 

It's a chinese pot from ebay no marking other than 500k...

But what I find confusing is that it behaves as an audio pot when used as volume and like a linear when used as tone pot