well, I was going to say the early period is key because batsmen did seem to be able to play this wicket with a little settling time.
so, er, that's not so good losing williamson in the first over but no sign of a panic so maybe it wasn't that key. (I think "first period is key" is a bit of a cliche anyway, of course losing lots of wickets in the first hour is bad and putting a fifty partnership together is good, so it is sort of stating the bleeding obvious.)