I'm not sure what you mean by "the shape has never recovered."

H. sempervirens is a cool season grass which can be cut back to inches 2-3 times a year, and should be at least once a year, in late winter. Each time you do it, new foliage will flush out.

If the part of the grass you cut back did not push up new foliage, chances are that part of the crown is dead.

If this is the case, dig the plant up and divide it, discarding the dead portions of the crown, and re-planting the divisions of the good portion.

I always thought that cutting it back the way I do with other grasses is a no-no with this one. Thanks.
I will dig it up and cut away the dead parts and replant (hoping for the best).