I did a very quick visual check of the pool at the Dublin Clarion IFSC, and my earlier suspicions were correct. The pool as well as an attached fitness center, sauna, and spa are all part of an independent operation in the basement of the hotel building. You ride the elevator to the basement, and your room key is your complimentary pass into the spa/health club; there's also a separate street entrance for locals. As with the rooms, the spa/pool/health club are above the standard you'd expect of a domestic Clarion.
Breakfast is not included with an award redemption. There's a good Irish breakfast buffet that costs 12 euro and has all of the elements of the "full Irish": eggs, bacon, sausage, broiled tomatoes, sauteed mushrooms, fried potatoes, fresh fruit, several types of cereal, toast, pastries, juices, coffee, and tea. The buffet area turns into the Kudos restaurant at night, which we did not try, and adjoins the Kudos bar, where we stopped late on Friday evening. The bar was nice--and it is a bar, no faux Irish pub here. Relatively busy for a hotel bar, but there may have been business types unwinding after meetings at the hotel all day.
Again, I am very impressed by this hotel. Highly recommended if you're ever in Dublin.