The grab is less stable with wrists contracted than with wrists relaxed/held/extended.
Not having an advantage does not mean you will have a guaranteed disadvantage.
You both start the same way and then you try to (hip)throw/suplex your opponent to win.
The same way, assuming the other doesnt contract wrist, but what if he does? Can't think of anyway to counter that.
because contracting wrists is as lame as using shovel and obviously have nothing to do with skill. if you rely on it to win - you clearly aren't good in aikido.