I'm surprised I've not seen this thread before...
I've read the Tarot since the mid and latter 1970s and been a professional Reader since the early/mid-80s.
Now, before we get all kinds of cynical rhetoric flowing (which seems to have already been barfed up earlier
) I am likewise a veteran of the magician's world and more than familiar with all the skeptical "explanations" to it all... most of which have been shared with the world by individuals who've never actually worked as a full-time Reader, nor have they studied any of the oracular systems in-depth... this is obvious when you have people like Joe Nichols saying that you don't need to know the meanings of the lines in a palm, what the cards mean, etc. I can assure you, in the real world if you attempted such stupidity the patrons of the psychic world would eat you alive.
My accuracy with Readings depends on the situation and now days, how I'm feeling; on a bad day I'm probably hovering between 75-83% on the scale whereas my good days can get me up into the lower 90% BUT, and this is the important thing cynics love to ignore, skirt around, down play, etc. The Tarot IS NO the same thing as Prophecy; it is Divination, which leaves the sitter with their free will e.g. nothing is carved in stone and any sense of foresight can be altered by the sitter, though it's not quite as easy as turning left instead of right when you leave the Reading. If something is supposed to happen in your life or affect your life as per the Reading, it will. BUT (again) there are variables, the biggest being if or not you are getting your Reading done by someone that does the cards by rote, based solely on their book meanings and methodology, OR are you getting a Reading by someone learned in the cards as well as a sense of intuition or empathic connection (a.k.a. "Psychic"). It is only with the latter that you are going to run into those harder-hitting, more influential "predictions" as they were.
Prophecy
IS NOT the same things as Divination though a huge majority of folk misunderstand that fact; mainly due to dime story novelist & Hollywood's misrepresentation but likewise due to both, religious and skeptical rhetoric in which this contrast is deliberately obscured for the sake of proving personal/cult biased views.
YES, there are frauds out there as well as delusional air-heads that think they are Psychic or "gifted" in some manner, I will not disagree with such observations and will in fact sustain them. However, there are likewise those in this great big world who are not out to make a name for themselves, nor do they charge exorbitant fees for their work (most don't charge anything) and who are essentially what they claim; a sounding board available to help those that need the help and guidance. They are individuals blessed with some sense of insight or awareness that skeptics/cynics can readily explain away nor can the magician replicate... and before it's stated, NO they are not the sort that would subject themselves to the stupidity of some bloody series of tests, they view that sort of thing as being both, foolish and glory seeking, nothing more! These folks do not seek out the lime-light, most are actually reclusive and live a rather quiet, simple life.
So, when it comes to Winston's question; yes, the Tarot (or most any other oracle) can be amazingly accurate when in the hands of someone that understands said system as well as the supportive elements associated with it.