There is not much, I can add.
"The first move is a tsuki", I read recently. And I do not see, why most of you thought, it could only be the free hand.
Well to me the phrase is quite familiar. generally said: "Uke should not try to loose contact, as he has to protect himself. If not he might get pain." In some kokyu-nage we are told: "If you do not jump, I 'll grap your balls."
But this phrase is followed by:
"Naturally in Aikido we do not do this (hurt, kill, etc.). We change the technique. But at the moment we are practicing this shiho-nage and uke should behave well." It is not that sensei is repeating this in each time, but often enough that no one of us should be confused. So in each lesson where such techniques are trained more often, at least once.
So just saying " Now, if u dont continue to hold on to my wrist, then i'm going to poke out your eyes w/my fingers", should have a plan B.If you are attacked by a much stronger, well trained or armed fellow, and you do not have the skills to change, but the attacker does not hold your wrist, yes punch with your fingers into the eyes or wherever you get him.
In training you do it step by step, and when you are confident in the uke's grip you can increase the power of the atemi, always being ready to stop to avoid accidents.
Perhaps you might be faced to a drunk, weak person, who just graps your hand to talk to you, but of course, you do not like it. You try a light shiho-nage, just to make clear your wishes, but as "uke" does not grip firmly, you poke out his/her eyes.
Legal aspects may differ from country to country, but that is definitely not the "do" of "aiki" that I want to go.
Well the example is somehow extreme. I just wanted to point out that the idea is understood as common for Aikido, and I accept that 30 minutes are not enough to explain each aspect in detail. But a teacher should be careful with what his students might understand and what might be results.
Greetings
Dirk