Topband: Submerging variable caps in oil as substituteforvacuum variables

[Tom W8JI]

> Very true but the RF is still in the oil "dielectric" from the coax 
> connector to the hot end of the resistor.
>

Not the same at all.

Loss tangent is meaningless in the dummy load application because impedance 
is low (weak electric field). There is very little displacement current 
compared to current into the resistor.

Loss tangent means everything in a capacitor in a coupling or tuning system, 
because displacement current is as high as or higher than the terminal 
current.