Doesn't work like that. Just because he had a career year (really 1.5 months) doesn't mean he will do it next year. Lets not forget he hit like dogshit in the playoffs and was pretty much an automatic out.
Like I mentioned earlier even if Goins say puts up 1 WAR and Tulo puts up 3 WAR. You lose more than 2 WAR of production to the team. Since Tulo is so much better of a hitter than Goins, that creates more PA for the top of the lineup (JD, Bautista etc..) which will be shown in their WAR totals.