The only thing I can think of would be that if you've become stronger during the offseason due to a particular training regime, perhaps it's difficult to adjust your timing and swing speed based on the fact that it doesn't take as much effort to generate power.
Or, you know, she wasn't able to get in a solid (regular) offseason fitness thing because of the exo, Fed Cup and the Czech extraliga and everything's all screwy now.
I think its' this!!!!!!!
Cause the weight training (even high rep, low weight), I think would more create the situation you described.
Nonetheless, like you, I think it's the result of lack of preparation time due to the Exo (which I forgot), Fed Cup, Czech Extraliga (which I almost forgot), and all that other BS she shouldn't have participated in.
And remember, this woman was sick, and should have been recovering, so she would have had full time to recuperate, and prepare for the new season.
Anyway, hopefully she wins tonight. Because if she doesn't; this thing is gonna really blow up!!!
Once again: What a Clusterfuck (her team)!!