I'll give the comedians a bit of a pass. Usually they do two shows at two different times to accommodate traditional diners eating at the two different seatings. On Ruby these shows were also held in the smaller Explorers Lounge and there is not a lot of room anyway.
A Bad Day At Sea [with power] Always Beats A Good Day At Work
Carnival: Glory 2004, Destiny 2008, Splendor 2009, Freedom 2011, Valor 2012, Dream 2013
Celebrity: Summit 2011
Princess: Ruby 2010, 2014, Caribbean 2013, Coral 2014