The wider the rear of a monocoque shell saddle (vs. a tensioned leather saddle with a rear cantle plate), it appears, the more gradual the transition to the nose has to be in order to support the "wings." So if you need a very T-shaped saddle, I'd agree with Muirenn that you want to be looking at models that are narrower in the rear and that "men's" saddles are an option for you.
Last year SI came out with the "SLR Monolink Friction Free" which advertises a much sharper T-shape. If you sit more upright this saddle might be too narrow for you, but if you sit more toward the narrower forward parts of your sitbones it could be worth a look. Some SI dealers have test kits, though I'm not sure whether they include that particular saddle or not.
ETA - haha, great minds think alike.
I'll hazard a guess that the reason you feel like you're too wide for the more wedge-shaped saddles, is that the wedge forces you forward so that you're sitting on the nose rather than on the wide rear. That's how it works for me.
Last edited by OakLeaf; 01-16-2012 at 05:51 AM.
Speed comes from what you put behind you. - Judi Ketteler