  We regard Forcing Notions P adding real numbers and the algebras of
P-measurable sets. As for Cohen- and Random-Forcing we can show that each
analytic set is P-measurable using Solovay's Unfolding Trick for infinite
games. To show this we develop the notion of strategic fusion and give a proof
of a uniform unfolding theorem which allows us to reduce the proof of analytic
measurability to the definition of a certain function.
