When thicker strokes are rendered slowly, it appears to have a weird rough edge along the stroke, and on the tips. It seems the system is drawing the thinner internal stroke, then just overlaying it with the thicker one. While it's doing this there is a weird transparent area between the thick and thin stroke as you can see in the tips of the stroke on the right.
is there any work around to this?
Currently, this is indeed due to our stroker.
The solution could consist in implementing your own stroker using the IStrokerFactory interface: https://developer.myscript.com/refguides/interactive-ink/android/1.1/com/myscript/iink/graphics/IStrokerFactory.html