The 2014 Royals postseason run is a good illustration of how fast baseball has changed. The last time that an AL Central team came out of nowhere to sweep the ALCS and go to the World Series was 2006.
The Royals weren't nearly as bad last year as the Tigers had been before 2006, but they're both big surprises. In 2006, the Tigers had the #1 team ERA in baseball at 3.84, and had 6.23 K/9 (ranked 23rd). The 2014 Royals ranked 12th in team ERA at 3.51, and had a K/9 of 7.25 (ranked 24th).
How would the 2006 Tigers have ranked in 2014? Their team ERA of 3.84 would have been ranked 21st. Their K/9 of 6.23 would have been ranked 30th. In 2006, the Tigers had a somewhat dominant bullpen, with a Batting Average Against of .242, which was ranked #2 in baseball. In 2014, that would have been tied for 19th. The 2014 Royals had a BAA in their bullpen of .235, which was good enough for 11th in 2014, but would have been ranked #1 in 2006.
Yes, 2006 was a while back, but it isn't ancient history. The only remaining player on the Tigers from the 2006 Tigers is Justin Verlander, but they're still on a run started by that team (although it might be petering out). What were considered good pitching stats in 2006 would be considered mediocre at best today, and sometimes downright awful.
The Royals also ranked 14th in runs scored this year (651), which would have ranked dead last in 2006. The game has changed and the Royals are a great indication of how quickly it has happened.