There is no reason for Universal to "test" multiple shows for HHN. This event has always thrived on shows/entertainment offerings (just like Orlando) and has had multiple in the past (just like Orlando). Here is a brief recap..
1992 had 14 shows/entertainment offerings, a DJ area called "Club Fright", along with 2 mazes, the Terror Tram, 2 rides/attractions
1997 had 7 shows/entertainment offerings, 4 mazes, 1 ride
1998 had 7 shows/entertainment offerings, 4 mazes, 2 rides
1999 had 5 shows/entertainment offerings, 5 mazes, 3 rides
2000 had 5 shows/entertainment offerings, DJ area called "Dance Party", 5 mazes, 3 rides/attractions, 1 SZ
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2006 had 5 shows, 5 SZs, 2 mazes, terror tram, 4 rides
2007 had 4 shows, 5 SZs, 4 mazes, terror tram, 3 rides
2008 had 4 shows, 6 SZs, 4 mazes, terror tram, 4 rides
2009 had 2 shows, 6 SZs, 4 mazes, terror tram, 3 rides
Then there has been only 1 show since 2010, except for last year which had no show. -sigh- So while mazes have increased in number, its disappointing to see just how much content has been decreased over the years... First shows, now SZs too.. :unsure: