Gary,
So for repair reasons, and heat transfer to the ground planes is increased, 
thus making the smt component removal more difficult  - that's one reason
to use thermals on vias.

But isn't it typically the rule that a 10 mil trace connected to a 50 mil pitch 
SMD land (28 mil wide) with the via about 15 mils away constitutes/substitues for
a thermal relief in itself? I haven't heard too many complaints from our assembly
house(s) nor from the repair personnel while repairing the boards. I've heard some
complaints from them for BGA repair but nothing else...

As far as the movement of copper/matl on inner layers during the handling/heating/cooling/
solderwave/etc... assembly ops in general - and the increased stress of direct connections
vs thermal relief around these vias - I would have to say that unless the standard materials
used to build tehse boards are not in conformance with today's standard assembly operations -
and move to the degree where a direct connection could somehow crack away or be damaged - then
well I guess we will all have to use "work arounds" like putting thermals on vias because of it.
I don't buy it.

Tom

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