First of all I never said anything about Smith though just Kuemper. Also the stat seems to mostly correlate with what happens? Binnington is probably the overall best goaltender at playing the puck at a high rate while being efficient, which was on full display both during their 2019 Cup run and was causing Colorado's dump and chase nightmares this year. Smith has the highest volume of playing the puck in the entire NHL which means he also does it in more dangerous situations than anyone else leading to lower efficiency. Kuemper meanwhile never plays the puck whatsoever and also doesn't tend to do much with it when he does. As for measuring how well the D get the puck out, Colorado's defense includes Makar/Toews/Byram, I think we can safely say that they're better than most teams at transitioning the puck out.