Just some information on this...Consider that the theory behind most dive computers is over 50 years old, and many of the theories have problems with band-aid fixes on them.
Different computers use different models, or Algorithms, pretty much all of which were developed in the last 30 years or so, not 50. These include the DSAT, RGBM, VPM, and Buhlmann models. All of these have been adjusted to different degrees over the years as a result of further research.
The original version of Ratio Deco was designed to approximate a Buhlmann computer program that was tweaked in accordance with the then popular theory of deep stops. The UTD version is different from that. It used a much deeper version of the deep stops theory than any of the other deep stops programs, like VPM and RGBM.
Research over the last decade has made the deep stops theory look less appealing, and divers are moving away from it rapidly. If you go to the technical diving forum in ScubaBoard and look for the deep stops threads, you can follow the debate. Right now the most popular theory among technical divers is the older Buhlmann algorithm tweaked with what are called gradient factors that are much farther away from the deep stops model that was popular just a couple of years ago.
The Ratio Deco system I was taught when i was a UTD student was very, very much a deep stop program. It was recently scientifically tested in comparison with a Buhlmann algorithm also tweaked to be a deep stop program, although not as deep as Ratio Deco. Ratio Deco came out very poorly in that comparison. I have been told that as a result, UTD has made a newer version that is not quite as deep, but still much deeper than the algorithms currently favored by most technical divers.