Originally Posted by NadalAgassi
Chris's overly generous humility aside, Navratilova's slam losses to the likes of Sukova and Kathy Horvath in her 2 best years ever in contrast to Evert's historic semifinal streak, historic stretch of winning atleast 1 slam per year, and 12 years ranked #1 or #2 every week, suggest otherwise.
I wonder when Chris said this, and in what context. I think there was certainly a period when in the course of their head to head rivalry it was true, and it may have been true in general for that period from 83-87. Martina's loss to Horvath was an obvious anomaly, considering the streaks on either side of it. Sukova was a semifinal loss, not a 2nd rounder.
As for their careers, definitely not. Martina's highs were higher and her lows were lower. As you said, Evert was the most consistent champion of all time. In part because so little in her game could go so very far south. It was a basic machine with very few complicated or intricate parts. The gears were always well lubricated with perfect fundamentals and technique from the footwork to the stroke production so that even if her confidence was off or she was distracted, a chunk of errors or problems just could not contribute to losses. The space between Evert's very best tennis and her very worse was the smallest of any champion's until very late in her career.
But the Op asks a slightly different question than cannot be answered by consistency alone. It presupposes a style that can and will go off kilter periodically, either because of the timing required by the stroke production, or the margin of error in them, or the complicated tactics or patterns or concentration lapses or fitness issues. It then asks the question how well can the player fix the problems or right the ship in time before sinking. It does not speak to losses that will come even when your game is sound, but your opponent is playing the best stuff they have played all year. Those occasions when you are playing someone on a hot streak.