It felt so nerve-wracking watching the last 15 min last season having the fear that eventually the opponent will score and turn the game around.
I for one have just realized that this feeling is long gone, so I checked the goals conceded in the last 15 min for this season and last season to reassure my observations: We were 9-18 last season compared to 8-5 this season in the 76-90th min in terms of goals scored vs goals conceded. On top of that, we were 9-15 during the 61-75th min last season, and we turned it into 8-3 this season.
Maybe Smith has got a point not using subs.