FWIW, the reason the "passing the physical" was mentioned specifically, in the 2012 offseason, Lechler had an "undisclosed" left knee arthroscopy and missed TC on the "non-football injury list." He missed the first 2 preseason games. However subsequently went on to play in the 3rd and 4th and all 16 regular season games quite commendably.
An interesting ESPN piece from August 2012:
Punter Ranks: Shane Lechler No. 1
(the rest of the top rankings are analyzed within the link)
Like with kickers, this is not a glamorous position and they are often only noticed when they screw something up. But having a great punter like Shane Lechler or Andy Lee can be a fantastic way to dominate field position with a booming punt or great directional punting to pin the opponent deep in their own end. A great punter can be a defense's best friend. And, for that matter, an offense's too.
Think about it. If you pin an opponent deep with a punt and hold them defensively, you gain field position while your offense sits on the sidelines. Combine a great punter with a big-legged kicker and it can add more than a few field goals to a team's point total by the end of the season.
Unlike with kickers though, punters need to be very good athletes. It can be a huge help with wayward snaps, trick plays and potentially making a game-saving tackle as the last layer of defense. All of those elements figure into the rankings below.
Lechler is a strong-legged punter who has learned how to be an accurate one as well, trying to hit the coffin corners or getting extra hang time on shorter punts.
He is a right-footed, three-step punter with excellent mechanics and a high follow through. He can speed up his motion when under pressure. He has solid hands and holds for field goals and PAT attempts.