Hi Larry, I have dense soil and the roots on my plants are also dense as a result. I wouldn't cut any roots off, I would just plant without a dome. The density will not cause root rot, the roots are plenty healthy. The growth from this point forward will conform to the new growing conditions.
I visited a Daylily Farm to pick up a cultivar. The grower grew in compost and did not water. Some of those roots were over a foot long. Denser soil retains moisture and the roots don't have to travel far, but can produce many. The aforementioned Farm plants root system compensated for lack of watering by travelling far to seek moisture, producing far fewer roots.
