If you are constantly playing at a high level, acquiring a DLC course and completing well can certainly assist you achieve your goals quicker, but it will not at all hurt you compared to the rest of the field. The flip side of this is that if you disburse for a DLC course and play badly, you could actually harm your ranking. This follows the actual threat/reward that professional golfers have to weigh while deciding whether or not to play in an event.
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