Iron eagle and Da Rock,

I was meaning balance and servo tabs of some sort, but I didn't write it very clearly. I agree with Pimmnz, they are very common right up to modern aircraft including those with hydraulically boosted controls.

Iron Eagle I guess you meant to say the Golden age prior to WW II.

Dave H
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Yes in the period after WWI and before WWII...

The type of tabs I refer to as "boost tabs" used the tab surface to offset the force the pilot felt on the stick.