There is no comparable test method for a fully loaded stove run at high output that I know of. The fuel charge volume is strictly limited in EPA testing. Additionally, most stoves do not have a thermostat limiting the top output. That can be both a plus and a minus. A BK stove is not likely to run away like a poorly attended non-thermostatic stove can. A properly run, non-thermostatic stove can often be pushed hotter as long as one stays below a safe maximum temperature. If the stove is unshielded, the radiant heat can be high.Are they "somewhat lower" on the high end? Are they based upon the same method? If not, then the values are not comparable. We certainly do not make the highest BTU producing stoves, but if comparable test method data is used, the difference is negligible.
BKVP