Karl,

Thermal releifs on plated through holes, in general, are required when
attempting to solder a component lead in a hole that is connected to a large
copper area (ie. plane). If you are not soldering something into a hole, such
as noraml interconnect vias, thermal relief is not necessary. If you are
attempting to solder fill a vias for test purposes, then you may have to
continue thermal relieving.

Regards,

Gary Ferrari
Tech Circuits
203 269-3311