So, just a random observation for consideration/discussion.
I was cleaning my cellar last night boxing up lambic to be relocated. I found a bottle of '09 girardin that I placed upright on a shelf and it has sat undisturbed for the past 5 years. Looking at the bottle closely, you can see some evaporation has taken place. The current liquid level on the bottle is a solid inch lower than the line where the pellicle formed and stuck to the glass initially.
I dont believe laying down bottles is any better than storing them upright but I found this to be interesting enough to share. Especially since my cellar is not dry, it is humid enough that corks drying out should not be an issue. Now im just left wondering if the bottle was on it's side this entire time, would the evaporation have been the same amount or possibly less/more.