Re: Ukemi: pluses and minuses
Being Uke, when done correctly teaches us to yield to forces greater then ourselves. Good Uke's, during something like jiyuwaza, don't give up their center, but they do give up their ground. You cannot stand your ground if something has more force then you do, but you can keep your center while giving up your ground. A centered Uke takes soft controlled falls, an Uke without center spats onto the mat in a loud thump.
Ukemi teaches us one half of Aikido, I know it's a cliche', but it is so for a reason.