>	Question is: could a stuck thermostat have caused the head 
>gasket to blow...?

I think you would have seen it running way hotter than usual after <10 
minutes if the thermostat was blocked.  How has it been in week or so 
before? low coolant can lead to that gauge behaviour when the pump can't get 
enough water to circulate (due to airbubble) you may need to retorque the 
heads, maybe it will come back fine?  Better land that VW job and get the 
parts cheap, quit later if the job stinks :), bye tim