Whoever claims to know where the dollar is going is either a charlatan or delusional. Unless it's me, in which case being wrong will do.
But on any rational argument, it's too high. Even the Reserve Bank thinks it should be at 90-something cents against the US dollar.
So whatever you plan on doing about it - visit Paris, buy a new car or, I hope, invest - will be a great deal. If you take the travel option, research group Canstar says the Cash Passport debit card is cheaper than using travellers' cheques or credit cards.
Hmm, cash would be cheaper still. Either way, it's best to buy half now and the other half just before you leave - that way you halve your chances of exchange-rate rage while abroad.
So has the dollar peaked? Goodness knows. There are any number of logical reasons, ranging from our relatively high interest rates attracting offshore money that can't earn anything at home, to it being a gateway to Asian currencies riding China's great industrialisation, for it to keep rising.
Sorry to be unhelpful but any one, none or all of these might hold the key.
It's also uncanny the way the dollar follows the fortunes of Wall Street, so maybe the dollar is just a proxy - or plaything more like it - for what everybody else is thinking about the economic outlook. Not ours but theirs.
Central banks are buying the dollar as well to avoid holding more US dollars or euros with their rotten credit ratings, and there must be only so much non-income earning gold they want to hold.
For all that, the real game-changer is the currency war being waged by the US, Europe and Japan.
They're pumping up their sluggish or shrinking economies by printing more money. After all, running even larger budget deficits when their debt is so high wouldn't go down well with the global banking system, and so plan B it is.
Since their currencies can't exactly fall against each other simultaneously, that leaves whatever is left standing - the only one not being manipulated by a central bank. You guessed it.
No wonder the dollar is hovering near a record on the trade-weighted index that measures its overall value. Having never reached so high, let alone for reasons that have little to do with it, also makes the dollar's impact on investing less predictable.
Who would have guessed five years ago that bank shares would be the undisputed winners, or retailers the standout losers, from a strong dollar? Yet the banks are attracting foreign money with their high dividends like moths to a light, while shop mall retailers have been struggling with even cheaper online competition.
So when choosing a stock, the outlook for the dollar should be the last consideration because its value no longer has much to do with where the economy is going.
There's just one exception - you can buy shares in exchange-traded funds that hold only US dollars, sterling or what have you. Their values rise or fall, cent for cent, with the exchange rate.
Anyway, it makes more sense to invest in international shares or property because at least you earn an income, too.
You'd be getting in on the cheap with the bonus of a capital gain and higher regular income if the dollar ever falls.
There's just one niggling doubt. If money is pouring in from offshore because our market is a better bet, why buck the trend?
Read David Potts in Sunday Money, every week in The Sunday Age.
Twitter @money potts