It seems reasonable to me if you were trading on multiple timeframes. For instance if you took a trade based on a monthly chart and then in the middle of a month you saw a trade signal in the opposite direction on the 4-hour that wasn't big enough to have you close the entire monthly trade so you got in and out while your monthly trade was still going. Given position size calculating and having different exit strategies and signals to your entries and all that, it seems simpler to hedge rather than closing and reopening a position and furthermore when you're trading a monthly time frame the spread is negligible.