I had tried something like that with MIN, but clamp does work better as it can stop in the negative direction as well.
| clamp(self.Width+handle.hor*dw,-Sprite.Max,Sprite.Max)
| clamp(self.Height+handle.ver*dh,-Sprite.Max,Sprite.Max)
But it has a quirk when you drag past the clamped size where it jumps around and flickers positive to negative sizes. Which led me to believe I must not know what's going on.