I don't think Wozniacki is a joke.
If anything, her #1 ranking says way more about the rest of the women's field than it does about her. All Woz does is turn up at each tourny and do the best she can with the game that she has.
The fact that none of the other players have been able to put the effort in outside of GS's shouldn't be taken out on Wozniacki. It's all the others that need to buck their ideas up, not her.
Look at all the seeds that fell in the FO...tells you everything about the flimsy nature of the typical top 20 female tennis player.