Definitely works. I pressure cooked 10+ year old black beans and they were crunchy. Did it the same with added baking soda and they were soft.
And like you I have a lot of 10 year old black beans and green lentils! (I have to be careful in pacing their use to 2 or 3 tablespoons at a time in something like lunchtime Raman or Soba noodles or I get complaints from Mrs. and Daughter.)