Good question. I know I'm not made of stone, by a long shot. Nor do I have any desire to be. The emotion and feeling involved, for me, is as vital (or more so) to me as thd physical. I've come across situations with subs like that in the past, and very quickly ended things, because I don't enjoy being treated like a stereotype or a trick. (For the purpose of clarification, I use "trick" to mean any sexual partner whose individuality isn't particularly important to the other.)

To the "fragile sub" point, my partner has suggested I need a Tonka truck sub. Versatile and virtually indestructible, because a broken toy is no fun for me to play with. So I'd certainly hope not all subs are fragile little flowers...