Totally missing the point of oil control. If the oil doesn't migrate out, the system wont need to go into oil return as much as other manufacturers. Also, it reduces the possibility of compressor failure due to lack of lubrication. especially when there are traps in the piping network. Since the compressors are always lubricated, the Toshiba can run harder at low ambient producing more heating capacity. Others have to go into step down mode and lose capacity. if oil stays in the compressors we have more heating capacity since we have more pure hot gas refrigerant which has a higher heat transfer rate . Also able to get a tighter control of the compressor frequency down to .1 Hz which allows complete closure of the eev