In reply to KG5OIB, my sense is that becoming really comfortable with CW after a certain age becomes less and less likely.
Having seen several folks in clubs diligently work at CW for a while it seems to me that the armchair CW
QSO experience happens only for those who acquired the skill at an early age. Those of us who attempt to pick it
up later in life find that a lot more continuing effort is involved, even with practice. Like mindless touch typing
and other semi-automatic mechanical skills there seems to be no substitute for early adult/teen acquisition.
I'm sure there are exceptions, but I haven't personally seen any folks who later in life picked up CW that now find
it effortless-unlike the folks in my club who learned early in life. YMMV.