We have already pre-stimulated

Prebuttal: Fiscal Policy Can Be Effective

We got a corporate tax cut which Krugman calls a sugar high, otherwise known as a stimulus. That corporate tax cut seems to have delayed the 2016 recession.

So, as Menzie looks to the future for more stimulus, we may be in an environment where the maximum good has already been achieved. We get a mild downturn and Congress overshoots the stimulus and multipliers go down.