Prior to alonso 2nd pit stop, it seems like MS can "barely"
match alonso's lap time. however when Alonso went in for his 2nd
pit stop, MS up the game with lap times about 0.45sec faster for
around 3 laps.
I believe Ferrari already know what MS and F248 is capable and they
have kept a low profile until renault 2nd pit stop to unlease the
true speed of the car.
As for why MS didnt want to over take Alonso in turn 1 and 13, I
believe it is because of the high risk and also strategy.