Headroom in Secondary

I've done searches on this topic but seem to be encountering conflicting information, so hopefully you guys can shed some light. I don't normally use a secondary unless I am adding additional elements to a beer (dryhopping, fruit etc), but I am wondering what effect my vessel is having on the beer. I've been using a large plastic wine fermenter with a lot of headroom (the container holds 2-3x the volume I'm filling it with). Now I understand that a layer of C02 will form in the primary to prevent oxygen contact, but that this shouldn't be the case in a secondary. How important is lack of headroom in a secondary?

That's a good question. I had always read that you wanted the smallest amount of head space possible, to prevent o2 contact. Yet, if you watch the video I link below, you will see Sam Adam's Jim Koch making home brew and in segments 8 & 9, you will see that he has a huge amount of head space. If it works ok for Jim, I see no reason to sweat it personally. As for me, I try to get the least amount of head space possible (aka more beer) in my secondary cause that just means more beer in the keg when I keg it all.

http://www.samueladams.com/promotions/PatriotHomebrew/video.aspx

I use secondaries and haven't found it to be an issue. As long as you have an air lock you are good to go.

HMM I would like an answer on this also as I am in the process of working out a trade .. 6- 6.5 gallon carboys for 6- 5 gallon ones to use for secondaries.

Ohio I love your quote