Think I mentioned it before in another thread but shoulder surgery is very difficult to come back from when a player's game is built around their serve - it took Sharapova at least a year to 18 months to be able serve anything like consistently again. All the breaks of serve suggest to me that Tara's ground strokes and return of serve are as ferocious as ever but that her own serve is now unreliable or weaker and easily broken in it's turn.