gEDA-user: [pcb] Using psbloat

[Dave N6NZ]

First time to try psbloat.  I'm going to see if it will help me generate 
a paste layer that I can laser cut into drafting mylar, and I need to 
skinny up the pads so that a lot less paste gets laid down.

So:
1. What are the units for the psbloat number?
2. Why does the dialog [20070912] reject negative values of psbloat, 
when the documentation says that is how you make thinks smaller?

-dave