Gone are the days when a flagship luxury sedan could stand on its own cosseting merits. Sport was a younger, coarser man?s game, played with lighter, lesser automobiles. Until it wasn?t. While Mercedes-Benz flirted with the concept starting in the ?60s and ?70s with its limo-powered 300SEL 6.3 and 450SEL 6.9, the idea didn?t really reach full bloom until Daimler bought up AMG. Lexus can?t stay entirely out of the fray, not in a time when Alpina puts out the quickest BMW we?ve ever tested in the form of a 7-series. Lexus?s last attempt at an F Sport LS, made during the previous generation?s refresh for the 2013 model year, was little more than an appearance job with slightly quicker reflexes. Even with the reduced expectations the designation carries versus the full-bore F badge, the result seemed more F Pastime than F Sport. Will the new F Sport, based on the radical new LS shown earlier this year, make good on a badge job?s promise" The F Sport can be had with either the standard twin-turbo V-6 or the hybrid powertrain. The power-hungry should note that the boosted 3.5-liter V-6?s output remains the same as the regular LS500’s, at 415 horsepower and 442 lb-ft of torque. Lexus claims that?s good for 4.5 seconds to 60 mph. The last LS460 F Sport we tested made the same run in six seconds.

The LS500h is not quite so aggro. The combined output from its naturally aspirated Atkinson-cycle 3.5 liter V-6 and electric motor amounts to 354 horsepower, which Lexus cla...