Seadog, I could instinctively turn away from an issue if I saw it e.g dense cloud, other aircraft, land mass, etc; but if instructed to do so my reaction time was pants!
In some ways it didn't make an overall difference to my piloting ability but it made a massive difference to my ability to be a student pilot and the understanding of my instructor.
It might sound silly to many people but not knowing left from right instinctively really is a pain in the bum!
Never worried about left and right when flying (er....is it left we go when meeting another plane head on ? !) but I found up and down a bit confusing! Seriously, it is possible not to know which way up you are; if you've ever been unlucky or reckless enough to be sucked up into a big storm cloud when glider flying, you may discover this.
you wouldn't know left from right under those circumstances either, I presume, but that's rather exceptional. Usually, people can tell up from down; the difficulty in telling left from right is that we are vertically symmetrical - one hand (one leg, one eye etc) for each.
I went in a shop some time ago and asked where I could find the canned drinks. The shop assistant said I'd find them on my left. I proceeded to the right, where the shop assistant quipped your other left!
Not being able to tell left from right ( without thinking hard about it) is a known condition. It is called "Confused laterality". I and all my female cousins suffer from it.
Some directions are instinctive - such as "up" and "down", "in front" and "behind", and nobody gets those confused. However, there is no instinctive reason why one side should have one name and the other side another name.
In some parts of the west indies, the locals refer to " leeward" and "windward" when they give directions. Try that !