I'm curious how do we know this? I don't plainly see this it all.
It was a while ago. But late last century the "line item veto" which allowed presidents to get rid of things in bills they didn't like was rejected by the courts. Oddly Reagan (R) asked for this power initially, but Clinton (D) ended up getting it.
https://en.wikipedia.org/wiki/Line-item_veto_in_the_United_S...
"Congress granted this power to the president by the Line Item Veto Act of 1996 to control "pork barrel spending", but in 1998 the U.S. Supreme Court ruled the act to be unconstitutional in 6–3 decision in Clinton v. City of New York.
The court found that exercise of the line-item veto is tantamount to a unilateral amendment or repeal by the executive of only parts of statutes authorizing federal spending, and therefore violated the Presentment Clause of the United States Constitution. Thus a federal line-item veto, at least in this particular formulation, would only be possible through a constitutional amendment. Prior to that ruling, President Clinton applied the line-item veto to the federal budget 82 times."
I think masklinn is arguing that, if Republican senators truly believed the president should be an elected king with nigh-limitless power, then during Democrat administrations they would have been eager to approve anything the president put forward, as he was the president-king at that time.
Whereas what we saw instead was them blocking everything they could, government shutdowns etc.
Unless "Unitary Executive" means something a good deal more nuanced than the president being king, that is.