Why would they do that?
To save their own life or to prevent themselves from being bashed? Should an experienced female Aikidoka consent to being raped rather than use Aikido to defend herself or her children? The point being that Aikido is purposed for repelling the attack of another person irrespective of what training that person has. O'Sensei as an elderly man is recorded as easilly overcoming younger much stronger opponents highly trained in Martial Arts.