I have a lot to say about this topic - and will try to keep it short.
First of all - when discussing hard limits...giving a reason for why something is a hard limit is imperative to me. For the most common hard limits I think we all understand why - they are either morally repugnant (children) or commonly disgusting and a disease issue (scat). But each person's individual, personal hard limits - you owe it to yourself and your Dom to talk about why. For example, one of my hard limits is fire play. It is an absolute, always, NO. Why? Because my twin daughters died in a fire. I'm not afraid of it...I simply do not and will not go there. The degree of openess that I must feel in my submission...the level to which I open my heart and mind to my Dom...tells me that I cannot know how I'd react to fire during play, and frankly, adding something to play that reminds of their death - how they died - and reminds me of the years it took me to learn to live with the loss would not be healthy mentally or emotionally for me. This is a hard limit that I have no fear he will ever, ever push.
The leash incident? Yes, he knew what I meant by the limit and knew that the leash was not the actual issue. Thank goodness! Because I do adore the leash.
As for Sir Russell's post...I believe that when we tell our Dom "I don't know if I would like that or if I could do that" - that's NOT a hard limit. It is simply expressing reservation or doubt. Isn't that one of the rewards of submission...to go beyond what we think we can do? To trust our Dom to know when to push, to know that we can do what we ourselves aren't sure of? I've read Sir Russell's posts for almost 2 years now, both here and on other forums, have talked with him as a friend...and if he were my Dom, I would trust him implicitly. I have never read anything he has written that has changed my mind on that.