but short is dominant in chis
long is ressessive, if your chi is long haired it deosnt carry for short.
there is a "brush coat" that occasionally shows up in chis but its a fault and i dont know what the genetics behind a "medium coat" are...mabe thats what your thinking about?
Coat Length
as a side note if your only concerns about a chi (long or otherwise are grooming and agility prospects...)
grooming for both coats is minimal...it takes me mabe 5 mns tops to comb out each wowie...(all 3 are longs) and another couple minutes for nails.
and while a chi will never run agility like a jrt or border collie, they are fast little dogs with alot of spunk and attitude, eager to please and suprisingly athletic...