The thing is that McLaren and the like typically aren't trying to 'gap' anyone, but rather keep up with the Red Bulls.
They weren't trying to gap anyone before the first round of pits...their first stints were both about getting past the slower cars.
And, as we've seen, a car on the hards is basically a sitting duck to anyone on even remotely good softs. Why not use the softs late, when everyone else is in 'cruise' mode and pick them off one by one? We keep seeing these cars on the faster tires later in the race chew through the field seemingly outta nowhere and always seem to end up much higher than the same-ol strategy bunch. And it makes sense. Track is more rubbered in, cars are lighter and therefore more able to take advantage of the extra grip, and the tires themselves have less stress put on them so they'll theoretically last longer.
If no one else, Mercedes should put this into practice, if not just to see what happens.