>If anyone has any experience with this,

My experience from the bare board building view is that without thermals
bare board yeilds may suffer because of localized delamination at drilling.  
Heat sinking at assembly should also be considered.  If you have the room
use a thermal area that gives an appropriate drill size target so the drill
does not hit the thermal 'ties' and deflect; causing misregistration for
vias below .018" drilled hole size.  I have run experiments with thermal
ties & no ties on the same layer with a marginal Oxide coating.  I got 100%
local delamination on the non-thermals and zero on the thermals.  Hole size
was 0.016" drilled.  About 3,000 holes total; 4 layer with heavy glass
construction.  I like thermals.  Thermals are good.  :) 

Tom Waznis
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 Hallmark Circuits Inc.
 San Diego, Ca. USA
 619-453-7800