This chicken farm tutorial was designed for survival multiplayer / smp where efficiency of a system counts more than compact neat looking designs. it is a little bulky but it delivers only what you want without having chicken glitching out and running around in your base or also delivering loads of raw chicken which need to get grilled first. So it is a "build and forget" design for it just works.
With the recent changes in Minecraft 1.5 also chicks when growing up to chickens have a hitbox change which pretty much renders all the compact snapshot designs useless for their efficency drops drastically because of all the chickens which die from suffocation damage. So in this tutorial we pretty much adapt what we had in the snapshots but combine it with a growup room and a flush mechanism... While altering the design we also make further changes to reduce even more lag by making the amount of seed chickens variable which suits us in an survival multiplayer environment
For the "real world" 10 seedchickens should be enough to get 2-5 grilled chickens about every half hour. + some eggs for cake or pumkin pies It sure could be compacted i will also play around with it before implementing into my smp world but for this video the focus was on providing a solution.