Dupe words. Bug or feature?

[cmawhorter]

var input = new Array(50).join('mom '); // mom mom mom mom ...
console.log(sw(input).sentiment); // 42.875

Because mom = 0.875 and 0.875 * 49.

console.log(sw("i distrust your mom and love my mom and her mom").sentiment); // 3

It seems like dupes should be removed or otherwise treated differently.