I live in an apartment with several other people, and we all contribute to the kitchen. I am a bit of a foodie (obviously, seeing as I read chowhound) and I brought a bunch of my favorite kitchen equipment, including my super sharp chef's knife. The other day I saw my roommate mincing garlic with my knife, and I'm pretty sure she has no knife skills to speak of. I was terrified watching her fingertips get so close. I don't care if she uses the knife, but I do not want to be responsible for any chopped off fingers. I tried to tell her that it would be better to curl her fingers under but she ignored my advice. I don't want to come off as a snob/know-it-all, but how can I tactfully tell her that she really needs to use proper knife skills?
Personally, the only person other than myself that uses my knives, is my Lady and she knows how sharp they are. She won't touch my Shuns, she knows how wicked sharp they are. What I did was purchase an inexpensive Santoku, that holds a good edge and I gave it to her. I sharpen it for her but I don't use it. Buy your roommate an inexpensive decent knife, give it to her and explain that she can use her own knife because you are concerned about her hurting herself with your knives because they are sharpened sharp and even you cut yourself if you are not concentrating on the job. Also have her watch the Shun video on Alton Brown's web site.
Assuming you aren't actually just a control freak, tell her to get her own knife or leave her alone. If she's damaging the knife (ie, trying to cut through bones or thwacking it hard on inappropriate surfaces) tell her to stop using it and probably, start keeping it in your room (playing favorites among a group of similarly situated people gets ugly fast.) Keep in mind that if she's old enough to be living on her own and knows how to mince garlic, she has probably figured out how to wield a knife to her satisfaction, if not yours.
I DID take the tip of my left index finger early last year. My elder son found it in the coriander I'd been chopping! The real fun started when the hospital used silver nitrate to try to stop the bleeding. I still don't understand what my kids found so amusing.
Roomies should probably not be exposed to a knife which can do that.
Incidentally, Nigella's Cuban Cure bean soup which I was making will never again taste the same as that batch did. I hope.
i'd keep my knife in my room. she might sue you if she hurts herself. (yes, i know it is hard to believe a lawyer would take such a case, ha!)
not a sermon, just a thought.
edit, in light of thew's observation:
roomie who has hurt herself with your super-sharp knife, talking to lawyer: "sivang never told me how dangerous it was, how sharp it was! you should've seen the blood, everywhere. oh, it was so shocking, i thought i was gonna bleed to death, just from that little cut. omg! i was weak, and dizzy. thank goodness my other roomie showed up to take me to the emergency room. it is still healing, see? it's taking such a long time, i can't really type at work. my workouts are on hold. i really am just having a hard adjustment to this. it's even numb sometimes. i don't know if it will ever get better. will you take my case? she never warned me!"
sivang to own lawyer: "i warned her, i tell you. i warned her more than 3 times!! i tried to help her by demonstrating how to use it, even"
cut-roomie, to own lawyer: "sivang showed me a way to cut, but it was dangerous -- and that knife, it is probably only for professionals. and now look at this big cut!!"
Please! I am always thrilled to hear the delightful ways people can fugure out how to blame a situation on lawyers. The truth is, if she is using your knife and cuts herself, there is no liability, unless the knife has a trick handle that folds up while you are using it if you don't know where the button is. My greater concern would be the potential for damage to a good knife when used by someone who doesn't have good skills. You expressed concern, which was not innappropriate. Now you need to decide whether your conscience will bother you if she cuts herself as that's the only responsibility you have.
truth is she's less likely to cut herself with a really sharp knife than a duller one. give her advice, but you cant force her to listen. after you've warned her, she's kinda on her own.