I still watch my colorised King Kong laserdisc from time to time. I remember Doug Pratt of the Laserdisc Newsletter prefaced his review of it with "Purists need not apply." Ha ha. KK and the Sony Blus of Harryhausen's colorized films are a pleasure, but I'd balk at a colorised Citizen Kane.
I have been thinking a lot lately about combining the chroma from the KK LD with the Warner BD. Unfortunately the cropping is different between the two so it would entail a lot of manual repositiong of the colours to really make it work. There are probably differences in the frame count between the two to also account for.
Not that I am in any way technically competent to do this, but the theory is sound. I was hoping dark_jedi and his team would tackle this, but as I understand it they need another project like they need a third ear :-)