Depends on whether you view the two sides as an equal threat or not
If they are an equal threat, then I agree as a draw means that your rivals collecitvely pick up 2 points, whereas one winning means that collectively they pick up 3
Here, I view Utd as a much bigger threat. They're roughly in the same position (Utd being 2 points behind with 1 game in hand over West Ham) but as I said above, the quality of their squad is a lot lot better than WEst Hams that if they click, they could hoover up points