If the Nats can advance past the first round and make a run at the big prize in either of the next two years, maybe you sit back and say this trade is win-win.
I just hate trades where if you don't win right away it has potential to be a deal you regret for years. If Nats have another '13/'15 season or continue first round struggles, it'll be uncomfortable watching Giolito and Lopez dealing for the White Sox because the Nats hit the panic button after their age 22 seasons.
One of the biggest problems with this trade is that the Nats aren't trading a pile of low-minors guys who wouldn't have contributed to their 2-year window. They traded at least 2 guys who would almost certainly have been on the MLB roster, possibly both in the rotation, in the second year of that window. Unless you think
right now Giolito's hurt or a confirmed bust, Lopez isn't a starter or a closer in the next 2 years, or both conditions are true, this is an overpay.