He is not paid to be the 5th option. Imo, more like a 3rd option.
At this point, even post TE-university, he is what he is going to ever be. If there isnt a poison pill in his contract, I would be in favor of trading him. This season, we need him to help Brown out. But in the off-season, get a stand alone RT and trade Knox. I hope Kincaid develops this year as a blocker and receiver as he has much better hands than Knox