I agree, MB, and w/ the other points you noted. AC had riders #3 & 4 right there, and... AS started the attack. What do you do, do the classy thing hoping that Samuel and Denis don't take off? They're 'only' 2+ minutes back, right, leaders of their own teams, and in one helluva battle for that last podium position.
A lot of this is just people, incl myself, wishing AC was a better patron instead of an obvious prick. ;>)
PS the only time I have not seen a rider wait for his competitor was when that rider was far off in the distance on a break away a la Vinokourov the day Beloki went down in the hot tarmac and Lance went Moto- cross.
Otherwise, they have always waited. Except for AC.