Yah... stations have bend doing that sort of thing forever. More recently, KKMO did the same thing. The announcer would barely say "kay", then much more loudly, "KAY EMM OH". Same with KKOL. Me?... I would never have let those 3-letter calls go in the first place. KXL and KGW (am) are others.
Not to belabor the KGY thread, but they've been creative with their audible positioning since someone there decided to adopt the "KAYO" concept without actually getting the call letters. All perfectly legal, so long as the top-of-hour is unambiguous.
If you go back far enough, you might remember "KOMO. TV, for Seattle", back when they all had staff announcers. I always did get a kick out of how solemn and serious some of those guys could be with their IDs... "Kay Eye Are Ohh Tee-Vee... Channel Sevennnnnnnn, Seattle!)