It may not be lol...but we are talking about a difference from just using expel harm right as the fight begins...which is what I said...to your suggestion of: enter combat, use expel harm, wait the 15, RL calls countdown...hit expel harm again (you may or may not get 4 chi, may end up with 3 chi)...then you gota get to the fight and use it. I'm just saying it seems a bit iffy for 1 extra chi...maybe 2...
But then again...thats my opinion lol. If it works for you, great. I said I will try. 15 seconds for the cooldown to go off and chi still remaining seems like a stretch. We'll see.