Sorry everyone, I should've worded my post better.
Whilst I have seen guys/ gals go to right seat of a jet off a piston it's definetly in the minority. 100% agreed.
My initial advice to TNB's thread was directed at either moving right seat of a Turbo-prop to Left seat OR right seat of a Jet.
Both are valuable moves.
A candidate already with eg. Brasilia F/O time and signifcant amount of Command Multi time either piston or light Turbine. Moving to Left seat of the Braz, Dash 8 etc very valuable experience OR right seat of their 1st Jet.
My opinion only RC