I dunno, I kinda agree with slower speeds on the S2S
the uphill curves after Squamish on a clear summer evening I along with another vehicle had tire blow outs from a football-sized rock...can't speak for the other vehicle but I was doing 100kph speed limit and eyes firmly on the road...by the time I saw it I thought it was a water bottle but in the split second decided it was safer running over it instead of swerving...not exactly a fun or safe place to swap tires in pitch black (good thing I had LED flares in my wheel well)
tl;dr there's tons of sweeping curves and you know in the winter people will attempt them near 100km/h with bald/summer tires...if this cuts down on the accidents and the subsequent bottlenecks, i'd rather get to my destination 5-10 minutes slower than have one evening where I get home 2 hrs later
but maybe keep the straightways at 100km/h or more
people who live in Squampton...too bad so sad