I too have been looking for a similar solution for a long time.
The only thing I have found so far is AVS4You Video Editor. It will get you want you need with fewer steps.
1. convert wtv to dvr-ms
2. load the dvr-ms into the AVS4You converter
3. select "Track 1" from the file info page
4. convert!
The original CC are converted to subtitles and burned in.
Let me know if this works for you or if you've found something better. I'd like to have something like this that is automated.