They’ve been doing a lot of interesting things with vision lately, and the Sporting News reports on performance-enhancing (i.e. tinted) contact lenses, the sort of equivalent of sunglasses for contact lenses… supposed to enhance your ability to pick up the ball in day games. Among the people that have been fitted for the lens are Arroyo, Timlin, Brian Roberts, and Junior Griffey.
I’m pretty certain that the lenses will be positive in preventing pterygium and other conditions related to sunlight exposure, but how much do they improve performance? Evidence seems inconclusive thus far - Roberts, the only one the article confirms as using the lenses during games, has no day-night split in OPS (day OPS this year: 1.262, night: 1.218), but he’s hitting a lot better (day BA: .429, night: .349). Interestingly, that’s not altogether incompatible with the findings that LASIK might improve BA and/or power, but not OBP - perhaps the way improved eyesight plays into hitting is in hitting good pitches to hit better, but not pitch recognition. But it’s early in the season, and so the usual small sample size warnings apply.
Pitchers like Arroyo and Timlin basically only benefit from the lens’ protecting them from the sun… more health than performance enhancement. The article implies that the amber-coloured lenses can have an intimidating effect, but if pitchers wanted to intimidate that way, they could already buy the contacts with freaky looks - the cat’s eye ones, for example. Actually, it might be funny if a pitcher started wearing cat’s eye lenses…