Bit of insight
The 5 man STB events when they started included a woodland and a speedball event. The team that top the table after the two events were then the STB chamipions based on two formats.
When the woodland died we moved to two events on speedball/suapir and to keep the two skills style format opted for a limited and open event.
Why 5 man , well it always has been as it gives teams with a larger squads chance to put two teams into an event, plus starting teams who have small squads can enter.
Change to 7 man - Whilst most say they want to play 7 man it is not working anymore. Last year the attendance reduced from 30-36 teams at the start of the year to 12-14 teams in the last couple of events. Yet event organisers running 5 man have 40+. As a result of this I was tempted to change all my events to 5 man but decided to keep the 7 man format for one more year - reduce the number of events but still keep the two 5 man events.
The 7 man format will be revieved as the 2006 year progresses.
I hope this answers your questions.
Steve