>>50409481Dug through the code and I believe yes, if a pokemon is listed in both land and water that means it's twice as likely to show up.
https://github.com/pokeclicker/pokeclicker/blob/f716028d0b289a81f4182609e68b2cf333d7e327/src/scripts/wildBattle/RouteHelper.ts this script shows that it creates getAvailablePokemonList by just straight concatenating the individual tables.
https://github.com/pokeclicker/pokeclicker/blob/f716028d0b289a81f4182609e68b2cf333d7e327/src/scripts/wildBattle/RouteData.ts This table shows that some pokemon are listed in both land and water tables, like you mentioned with Wingull (probably where the wiki gets its info).
https://github.com/pokeclicker/pokeclicker/blob/f716028d0b289a81f4182609e68b2cf333d7e327/src/scripts/pokemons/PokemonFactory.ts#L21 Finally this script shows that when you generate a wild encounter it just pulls a random result from getAvailablePokemonList without modifying it to remove duplicates prior to rolling.
I still think it'd be good for someone to idle on route 104 and count to verify, because I could be missing something elsewhere in the code that removes repeats
