UDT is basically the bare definition of reflective consistency: it is a non-solution, just statement of the problem in constructive form. UDT says that you should think exactly the same way as the “original” you thinks, which guarantees that the original you won’t be disappointed in your decisions (reflective consistency). It only looks good in comparison to other theories that fail this particular requirement, but otherwise are much more meaningful in their domains of application.
TDT fails reflective consistency in general, but offers a correct solution in a domain that is larger than those of other practically useful decision theories, while retaining their expressivity/efficiency (i.e. updating on graphical models).
UDT is basically the bare definition of reflective consistency: it is a non-solution, just statement of the problem in constructive form. UDT says that you should think exactly the same way as the “original” you thinks, which guarantees that the original you won’t be disappointed in your decisions (reflective consistency). It only looks good in comparison to other theories that fail this particular requirement, but otherwise are much more meaningful in their domains of application.
TDT fails reflective consistency in general, but offers a correct solution in a domain that is larger than those of other practically useful decision theories, while retaining their expressivity/efficiency (i.e. updating on graphical models).