Not sure why there was such a knee-jerk reaction, but it's actually fairly straight forward and not scammy at all. You're performing two trades, using a money market ETF that trades at the currency exchange rate, and paying standard brokerage fees + spread instead of currency conversion fees.
If you pay $20 in fees + spread for 2 trades, that'll be the cost of the conversion. For a $10k conversion, that's 0.2%. Unless you're suggesting that a money market ETF is prone to manipulation, your brokerage is going to scam you, or you don't like to deal with taxes on your stock purchases/sales, there isn't much drawback other than time. The larger the amount though, the more it'll potentially be worthwhile.
If you pay $20 in fees + spread for 2 trades, that'll be the cost of the conversion. For a $10k conversion, that's 0.2%. Unless you're suggesting that a money market ETF is prone to manipulation, your brokerage is going to scam you, or you don't like to deal with taxes on your stock purchases/sales, there isn't much drawback other than time. The larger the amount though, the more it'll potentially be worthwhile.
More info about this: http://www.theglobeandmail.com/globe-investor/norberts-smart... http://canadiancouchpotato.com/2013/12/03/norberts-gambit-th... http://www.finiki.org/wiki/Norbert's_gambit