I was actually stunned that Harris made the roster last year. Harris had a 51% catch rate last year and a 55% catch rate from the year before.
Watson's 77% catch rate last year is as good as it gets and I'm not sure thats what the Chiefs will get out of him. Watson is a year and a half older than Jason Witten so he is a risky depth signing but by all accounts should be a great locker room guy and should be able to replace Harris' small workload.