Yyyyes and no...the way you're describing seems like it's still building off the inherent bias against walk-ons, i.e. that no one doing a solo performance needs or deserves more than 30-45 seconds. Which is generally unfair. However, I also know of many competitions, even at international level, that DO add on incremental time for groups over 3, adding time per person, but they still have a max upper limit of anywhere from 2-3 minutes. But those competitions start out with a base time of 60 seconds for EVERYBODY. Group or solo, walk-on or skit, everybody gets treated the same up til 60 seconds. After that, you'd better have a group so huge that simply getting them to walk across stage will actually require an additional 30 seconds total.
I don't hold truck with the idea that extra people in your group require 30 seconds or more per person. I can see an additional 5-10 seconds per person up to a max capacity or max time limit, but that's assuming everyone starts out with a level playing field. I have seen groups that large, and yes, they really do require additional time for the mere purpose of allowing everyone to enter and exit stage. The point is, if you're not starting from an equal time limit in the first place, it still comes off as shafting walk-ons and solo performances.
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