Does it make sense?
Is this amateur night or what?
You go long and short the Euro at let's say 1.2700
The EUR/USD goes to 1.3000 so you lost 300 pips on the short side, plus spread and/or commissions, but you "won" 300 pips on the long side, so you close the "losing" side of the trade and you keep the "winning" side open, so total so far is zero, excluding the double commissions and/or spreads, right?
Then the EUR/USD goes to 1.2400 and you end up losing at least 300 pips on that cannot-fail trade.
Get it?
Now, if you are using options and want to bracket the market (because you are expecting great volatility for example) that's a different story...