Popular with Skyrim but would it work with MW?

I guess it might work. From what I understand from reading their http://www.hialgo.com/BoostFAQ.htm#Q_In_a_couple_of_words_how_does_dynamic_resolution_work, it's a program that intercepts information being sent to your GPU and dynamically lowers your resolution during "fast-paced moments". I'm guessing this wouldn't be very useful for Morrowind though, since its combat isn't exactly very demanding visually or mechanically.