My stuck M-2 tapers have had to put up with my learning ability.
Things I have learned:
Alway wipe the male taper with a rag and always wipe the inside of the female part of the taper Before inserting the tool. It only takes a couple seconds. Bradley formula, Undoing 1 stuck Morse = same amount of time as 75 cleanings.
For knock out I find that 10 or 15 "taps" work as well as one "whack" and is probably easier on the machinery. I move the knock out bar between taps so I get a tap on the right, then a tap on the left, then a tap at the top, etc. of the Morse's back end while doing this. For clarification, that tapping is inside of the fem taper. The taps are about the same rate as the shots out of a machine gun.
I usually just move the knock out tool in and out. If you use a hammer, steel is the banger of choice. It is that initial jolt, that a leather, copper, brass, etc. hammer cannot deliver, that does the job. Think of it this way---Would you rather be hit in the head with a 2 pound steel mallet or a 2 pound rubber mallet. The steel imparts a much faster and efficient initial movement from the hitter to the hittee (boy the spell checker sure didn't like that word).
I also store the Morse fittings where they do not get bumped and banged with other metal pieces and I refrain from letting ice cream, carmel, chop suey, etc. drip onto them when storing them.
To paraphrase my wife's brother, "That's (referring to the above) one darn fools opinion." Take it for what it is worth.
Enjoy,
JimB