Using Oxygen only slows the progression of altitude problems and if you have 100% O2, the partial pressure at around 0.3ATM is into the toxic zone - I suspect,

Using Oxygen only slows the progression of altitude problems and if you have 100% O2, the partial pressure at around 0.3ATM is into the toxic zone - I suspect, just like in SCUBA diving, these 'oxygen' tanks are an oxygen enriched mix. However, even if you deal with the breathing mix issue, you're trying to carry frozen bodies off a mountain while you've just encumbered yourself with a heavy cylinder and it's already difficult to move with all the clothing you need to wear to keep warm. If you ever have to move a dead body around, you will find it is quite difficult even with 2 people to help manoeuvre the body. I seriously doubt you would do anything more than end up as another statistic - just like the Nepalese police inspector and Sherpa the article described who tried to retrieve Hannelore Schmatz. In extreme environments, you do not always have the option for the civilized society niceties - they will kill you and, on Everest, leave you frozen to the spot.