One would think that the last 9 years was enough of a petrie dish to experiment on.
Our arguments always ended in the same place. You think that the deficits themselves are expansionary, while my position is the expansions are correlated to the cause of the deficit. If that deficit is caused by blow out spending, then don't hold your breath for an economic expansion. If the deficit is caused by tax cuts, then the private sector is motivated to increase economic activity.
I've been consistently saying since 2009 that Obama's "recovery" was a mirage and that's why growth didn't exceed 2%. For all his faults, Trump understands what motivates the private sector to invest and spend. That's why you're seeing faster economic growth now, despite coming on the heels of a 9-year "recovery." Will growth hit 5%-6% that he's talking about? Absolutely not. But anything over 3% is a home run.