(no direct dog in this fight, and I wish the best for the RAH folks)
Giving a pay raise to 10% of the people while negotiating a contract means management will have 10% of the vote going into a TA. So let's say the TA is marginal: under normal circumstances it may fail, but with all the FNGs voting "Yes" it could pass. With the buying-of-votes management is doing now, the group could end up with a Worse CBA than if there were no new hire pay raise. In any event, the raise WILL NOT yield a better contract. At best, it would be a break even.
Essentially, management is offering a "Zero down, No payments for three months" contract. They are selling you a car "for nothing" hoping you don't notice the 29% interest rate the remaining five years.