I'm convinced that extra day games was a huge liability as late as the early 2000's. Somewhere around 2015 they expanded it to 35 night games, leaving 46 day games. When you consider about half of those are played in April, May and September, I see it as an actual benefit for pitcher heath on cold nights. That's right, it changed in 2015? and then they won the world series. It WAS a liability.
From https://www.chicago.gov/dam/city/depts/oemc/general/PDF/2010WrigleyField.pdf
The 1988 Ordinance authorized 18 night games a year for 15 years (through 2002). The 2004 Ordinance allowed the Cubs to schedule up to 30 night games to be phased in by 2006 (with 22 night games in 2004 and 26 night games in 2005) at Wrigley Field during the regular season. The 2004 Ordinance extends through at least 2015.