How many rounds in a Swiss teams?

An issue that has come up at the Manly Leagues Bridge Club is the appropriate number of rounds in a Swiss Teams event. In particular is there a problem with playing too few or too many rounds - in terms of accuracy of the results and being able to use standard scoring programs such as ASE 8.

This article is a work in progress and I will edit it when I have more information. If others have information to add please do so in a comment and if appropriate I will incorporate it into the article itself.

Our particular issue was the combination of our existing practice of playing 9 eight board matches over three weeks with teams numbering from 12-16, and a suggestion that I received from a number of respected sources that this was over-Swissed and could reduce the accuracy of the final results as the leading teams played progressively weaker teams in the final rounds. Also suggested was the possibility that ASE 8 might fail to produce a swiss draw in the final rounds.

To resolve this issue and present a reasonable case to our players as to why we may need to change from their existing preferred practice I have tried to research this issue - with limited success.

It is also worth noting the options that with 13 teams it would be possible for us to play a 12x7 board round robin, with 4 matches on each night.

There is an excellent discussion of the minimum number of swiss rounds required, in the context of a major national event that produces a qualifying semifinals field at http://www.asecomputing.com/forums/showthread.php?t=450&highlight=rounds+give+chance&page=3, which tends to support the guideline that you should have at least log2^N + 2 where N is the number of teams - this would suggest at least 6 rounds for our 12-16 teams, and more generally 7 rounds for 17-32 teams and 8 rounds for 33-64 teams.

But this discussion did not address our question of possible issues with too many rounds (when the players want them).

I have raised the issue on the ABDA forum in >http://www.abda.org.au/forum/index.php?topic=121.0 and will update this article with any substantive reply.