Is part of the Initial purge line a pressure advance test?

Sometimes it makes narrow and thik lines as if it is a wrong pressure advance calibration, and sometimes it is perfectly straight

Is this a good way to verify the pressure advance is calibrated correctly?
By having a perfectly straight line?

Couldn’t find any information about this online.

Thanks.

No, not really. It’s just to clean nozzle and build up pressure correctly in order to get correct amount of plastic at starting point.

That’s what I initially thought

But first of all, with better calibrations i get a straighter line.

Also, if you watch it as it purges, you can see it starts stops and continues same as the pressure advance calibration.

If i am wrong i am wrong, but i am not sure of that.