What you are assuming is possible is a logical contradiction. To be able to recognise two persons as being the same is in fact the definition of de-anonymisation. Please check your math.
I'm not restricting my considerations to "the technology that is implemented and available to Tor users today", given that what's available neither meets the needs of sites, nor the needs of users. If you think that the idea is inappropriate, please state so and make your case for why you believe in your viewpoint. If you think that the idea is impossible, please note why you believe that — and then consider the idea as if it were possible.