Hi Anthony! Twenty five years ago I used to bike commute along the Mockingbird corridor from University Park to Stemmons at Empire Central. "Nasty road" is a pretty good characterization, that's fer sure. There were a few stretches of lightly traveled parallel streets, but not many.
I visited Dallas a couple of months ago and tried out the DART bus & rail routes, which came in after I moved away. It impressed me as overall a very nicely executed system, except that it is quite bike-unfriendly. It seems like it would be much better if they allowed roll-on / roll-off access for bikes on the trains and had bike racks on all the buses. And I don't see how it would be all that much more costly.