WDUV's dominance has to deal with a lot of issues including the following.
1) Signal, unlike the Riverview FM's WDUV packs a powerful signal into the North of the Bay Area. Which include the fast growing communities of Pasco and Hernando counties. Picking up the Riverview Stations from lets say Spring Hill is possible on an indoor radio, however it is such a chore. Back when I lived there if I wanted to listen to 101.5 I would have to constantly fiddle with the antenna. Wherelse WDUV's signal was strong enough to not have to fiddle with it. Fiddling with the radio is a lot of times too much effort for the casual listener. Not the mention the more elderly population is North of the Bay. Also people who may not overly care for "The Dove" may listen, like if its the least worst option that has an exceptional signal where their at.
2) Mass-appeal music, much of the music is very Middle of the Road and unoffensive. Even compared to the music on Mainstream AC's like sister station 94.9.
3) Limited DJ chatter and commercial interruption, some people just want music.
4) Imaging, if you ever listened to sister station "The Eagle" you would know. The Dove just has one person doing the prerecorded liners with no music or sound effects added. Where-else the imaging on "The Eagle" is louder and more annoying, especially with those "Eagle" screeches.
I like the station, just wish to playlist was wider with less predictability. Maybe another voice or two wouldn't hurt either. I would also summarize that "The Dove" puts a good signal over almost all of Hillsborough, Pinellas, Pasco and Hernando. If you include all 4 counties "The Dove" puts out more square miles of "City-Grade coverage" than any of the Riverview stations do. Riverview is in the southeastern end of the area. Pulling more signal out towards Orlando, Lakeland and Sarasota. Which BTW does not count towards ratings in the Tampa market.
105.5 BTW can't move farther south, its the protect the 105.5 in SWFL.