BarcampUKGovweb09/Comment and poll

The first BarcampUKGovweb had 50 session slots for around a hundred participants. Typically the sessions were 25 mins. BarcampUKGovweb09, although going on an hour longer, had only 30 slots for some 120 plus (?) participants. To me this ratio is getting just too far away from the spirit of barcamp: "8th Rule: ..., you HAVE to present. (Ok, you don't really HAVE to, but try to find someone to present with, or at least ask questions and be an interactive participant.)"
I agree there doesn't have to be anything like an exact equivalence of slots to participants and some encouragement of co-presenting is good, but with too few slots it's just getting too un barcamp. As Paul Canning comments: "This format doesn't work so well for the less confident.... I can think of a few people I know with much to contribute ... but far less skills to allow them to do it." Yes, I know you can put up a shorter session, but give the more strongly confident hour long slots and they will (and did) gobble them up.
If, as it seems to me, one of the things we're about is greater inclusivity and more active participation, then shouldn't we continue to ask ourselves if we really 'walk the talk'? If we are inclined to advocate greater inclusivity and more active participation more generally aren't we in a stronger position if we actually practice what we advocate? Many people seem to suggest that the breadth and variety of the group is its strength. Should we really be content to undervalue or waste some of that strength? Some of that fabulously rich pool of talent? Surely we don't want to drift back to some sort of spurious elitism or some sort of spurious hierarchy, do we?
Greater inclusivity is the main thing, but there are other reasons why shorter sessions can work better. Active listening for 25 to 30 mins is challenging enough, 5 consecutive hour long sessions is exceptionally challenging.
Too few slots and some presenters feel they have to all crowd into the last session. It looked like some attempted to squeeze four or five presentations together. The slot I went to was perfectly amicable and civilised, but I felt all were shortchanged as regards timing.
More presentations means a richer variety of topics and presentation styles. For me one of the highlights was the "multitude of hats" (think that was Paul Clarke?) session. One of the questions that often gets asked about these kinds of events is how can we sustain momentum. With more sessions we could have had for example, some sort of more relaxed, considered, review, recap, what are the options to take things forward type sessions at the end, instead of driving ourselves to an exhausted, abrupt stop.
=== Poll ===
The context: 6 rooms (2 larger than the rest), 5 hours and 120 participants. Slot length gives the following minimum proportions of those attending the opportunity to present (of course proportions are higher if people agree to co-present): 
* 20 min. 75% 
* 30 min. 50% 
* 40 min. around 33% 
* 60 min. 25% 
<poll>
Given the above context, what's the best length for slots on a barcamp's open grid?
20 min. 
30 min. 
40 min. 
60 min.
</poll>
category:UK events
category:Community involvement