How RF Choke doubles Vcc at collector in BJT Power Amplifier
Well, best to look at the problem as having 2 parts, DC and RF. Now if L is perfect then if there is any difference in the DC voltage between the collector and the supply then there will be a large DC current through the inductor.  Therefore av(Vc) = Vcc. (where av() is average over a cycle). Since we're talking about sine waves, and since the transistor's collector can't drop below 0, you get that Vc must have an amplitude of Vcc, ie it swings from 0 to 2Vcc so that it's average is Vcc.