@jwcph (a) yes, (b) no. The idea is to operationalise the nebulous question "can machines think?" by replacing it with "can a machine successfully play the Imitation Game?", just as Scoville operationalised "how hot is this pepper?" by replacing it with "by what factor must we dilute an extract of this pepper so that a panel of trained judges can no longer detect the heat?" Turing admits (page 2) that it may be possible to construct a machine whose operations are worthy of the name "thinking" but which cannot play the Imitation Game, but he thinks that if a machine can successfully play the Imitation Game against a sceptical judge, asking questions drawn from "almost any one of the fields of human endeavour that we wish to include", then whatever it's doing deserves to be called "thinking". That's a *much* harder challenge than producing text which is human-like enough to fool the casual observer: arguably that easier test was passed by Eugene Goostman back in 2014.
Anyway, I strongly recommend reading the paper: it's short, beautifully written, and answers most of the common objections that are raised to it. There's a copy at
https://courses.cs.umbc.edu/471/papers/turing.pdf.