Nobody's brought up the invitation of tori which lures ai-te to attack a specific part of the body.
When compared to working with boken, nobody in his right mind leaps forward and executes shomen or yokomen uchi (and thus be killed instantly
). Your attack is controlled by the opening(s) presented (or at least the ones you think are there
In turn that means you can control the possible attacks.
If you (as tori) lean forward ever so slightly and to either side, this might be perceived as a weak posture by ai-te and he will attack (yokomen).
Ai te may decide to change his attack at the last moment, from shomen to yokomen or other way around. This is actually very good practice and you'll find the is not much difference between them
Reversed yokomen with tanto