Any profit from the Fed goes back to the Treasury and seigniorage is basically a tax on all USD holders through inflation so it is largely a distinction without a difference. It is our money. Giving it back to us isn't a "loss".
Exactly right. But I'd even take it a step further, if we use that money to create material things like infrastructure (rather than endless financial instruments) is that really a loss? The dollar could cease to hold any value and we'd still have bridges and roads afterwards.
I might not have said it in that comment, but I totally agree with you. It is one thing to talk about the efficiency of government spending, but it is almost always stupid for us to talk about government programs or projects in terms of profits and losses.