@scale

 I can't believe I've never used @scale....

@pscale is useful for uniformly scaling the instance/copied object onto a point. But what if you need to adjust the scale on a per-axis basis?

@scale=set(1,2,3);

this will scale the object by 2 in the Y, and 3 in the Z

woop woop

vellum hair thickness

To randomise vellum hair thickness, you use pscale values. To get Vellum to recognise these values, UNTICK the Thickness box in the Vellum Constraints node.