There is a big help thread on KVS over in mileage run discussions.
As to what is going on under the hood, KVS is looking at the price to guess the L/M/H. As we all know, DL is not really following this too well, so KVS then has to punt.
There is no "magic" in KVS. It is just doing a more efficient job of asking dl.com for results.
I am not clear on the exact issue, but somehow they are saying you need to price by segment.