I'm not a DVC member, nor would I want to be. I much prefer making a cash reservation with the WDTC, with a pin code discount and getting daily housekeeping included, but...
My opinion on the use of the TWL exclusively by DVC members is that other than the community room amenities, the TWL lounge is just about the only other amenity for use by DVC members only.
Considering how much money DVC members have paid to join plus their yearly dues and the fact that daily housekeeping isn't included and they can't apply pin codes and discounts to their reservations, I feel the least Disney can do for them is give DVC members and their guests priority entry into the TWL.
Also, there are capacity restrictions in the TWL. However, when Disney better determines TWL daily use averages and sees that they aren't filling to capacity and they can therefore make a lot more money selling drinks and snacks, they'll definitely be letting ALL BLT guests up there - guaranteed

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