Nobody is arguing that DHS doesn't need capacity now. Closing nearly half the park at the same time to build new stuff was IMHO a foolish plan but it has little to do with cutting costs in 2017. If GMR sat idle for several years before construction started then you might have a case but not if they open the new ride in 2019 as scheduled. They closed it now so they would have enough time to finish the new ride for the SWL push not to cut current operating costs.
...of course its hard to argue logic with someone who still believes SW Land isn't actually being built in FL or at least will be delayed 5 years