First thing I have to say is that I totally LOL'd at Suz's post. Why? Because I think I have every single item she posted (except the boat neck top)... and even the same duplications (except only one of my three VC tube skirts are the same). Too funny.
I am a huge duplicator. And I'm not sure if it's a good or bad thing, for me. I do often find it quite hard to find things that I really like the fit of... I don't have patience to look hard, so when I find something, it's worth grabbing. Usually this is different colours, but the odd time I've got the same thing, when I can tell it's something that will be part of my life for a LONG time... my black v-neck BR linen tee, for example. Not trendy, and an essential. Yes, if I've duplicated colours there's a chance I'm going to wear one colour more than the others, but so what? If I'd bought a different whatever in that other colour, that doesn't mean I'd likely wear it more. I have no need to feel everything in my closet is worn equally.
And I totally get that having a duplicate gives you "permission" to wear something more often. I am also a saver, and I'm not sure why. But again, so what? I'd rather wear something I love more than save it, and if in effect buying two enables that, then just pretend the cost was twice what it was... still worth it? probably. As long as you have the space and budget.
What I do need to consider for myself is that with the advent of on-line shopping, and all my YLF influences, I shop more now than I did, and find things I like more than I did. So there is less need for me to duplicate just to save the time and effort of shopping. I have enough, so duplicating really does need the item to be amazing... no need at all to pick up more than one just in case I never find another white tee that fits me. Cuz I will. (Remember that, Elizabeth)