tube tent method?

[bov]

I'm distrustful; how would one get all the oxygen out?

 

[Aap]

While true that a large, sealed container full of an inert gas is a death trap for those inside (I read a story of several teens entering a very large helium filled balloon), this reference is poor in general, as you have highlighted the principal issue of completely flushing the container of residual air. The process would be different for a lighter or slightly heavier than air gas.

in the end, even entering the container would result in air entering. I would disagree that this is Easier than an exit bag, couldn't be faster due to residual air/air entering when you enter, and it poses a risk to those who discover your body.