Currently, the strategies are allowed to open only 1 position. Some strategies (with high SL) keep bad positions for weeks just waiting for the market to recover. If the strategy is generally good, it is blocked out from the market making other good choices for the period of waiting.
If a strategy could open multiple positions, it could, for example, reevaluate the market later and open either a different (hedging) position or a second position in the same direction, if it confirms the market trend further.
If implemented properly, this can be a good alternative to SL and can expand the scope of potential successful strategies and reduce risk for users.