After getting some feedback from post on playing to the score, I went back and took out all the empty-netters from my sample of third period statistics. Here are the revised totals for Belfour, Brodeur, Hasek, Joseph and Roy combined in the third period in the playoffs, from 1994-2008 (1997 not included):
Leading by 1 after 2 periods:
21 SF, 29 SA, 1.96 GF/60, 2.02 GA/60, 9.4% SH%, .930 SV%
Tied after 2 periods:
25 SF, 25 SA, 2.06 GF/60, 2.02 GA/60, 8.1% SH%, .920 SV%
Trailing by 1 after 2 periods:
29 SF, 22 SA, 2.59 GF/60, 1.76 GA/60, 8.8% SH%, .918 SV%
For comparison's sake, the average shooting percentage in the first period was 9% and the average save percentage was .920.
This is evidence that the team leading in the third period may have slightly better scoring and save percentages than the team trailing. The shots will usually favour the trailing team, meaning the trailing team is more likely to score the next goal. Despite this the team trailing after 2 periods won only 14% of the time, which shows the effectiveness of the tactic.
What is nice about these numbers is that the huge majority of the shots were taken 5 on 5, since the refs usually put away the whistles in the third period of playoff games.