Err... Earth sea level pressure is 1 bar, so Earth P - Mars P < 1 bar... Pressure don't care that it's "1/100 the pressure", 1 bar = 1 bar. The reason why the movies showing people exploding in space or on Mars are silly. The pressure differential will do some pretty ugly damage, given some time, but not instantly transform you in a blood balloon or a fountain of gore.
Yes, but he was not hyperventilating all the time, so the air pressure must be similar to earth. And they had that pressure exchange chamber.
I tell you, forget mars, that tape he was using is the ultimate answer! :)
I don't believe any space mission has ever placed humans in anything approaching "Earth normal", if by that you mean air pressure at sea level. Heck, even commercial aircraft don't maintain sea level pressures internally, as it's wholly unnecessary. In space, it is even less so. Commercial aircraft have to make do with the standard oxygen-nitrogen mix of the Earth's atmosphere, as well as being safe for infants, elderly, and people of various states of ill health. On space missions, these limitations do not apply. As such, the oxygen mixture is much richer, allowing the overall pressure to be far less, which in turn requires far less infrastructure to safely maintain the differential with low external pressures.
While Mars's atmosphere is minuscule in comparison to Earth, it is still a long way from being a vacuum. The pressure differential between the minimum pressure required for human life assuming control over the mixture, and that of the average surface pressure on Mars is certainly significant, but maybe not as significant as it may first appear. I certainly raised an eyebrow at the duct tape and plastic solution, but not so much so that I would condemn it out of hand. It is perhaps a bit of a strain on my credulity, but as a movie shorthand for a jury-rigged solution, I could live with it. I doubt it would be made a better film by having an added scene where Mark Watney mixed some adhesive to laminate the plastic as well as secure it more effectively.
If it weren't a fictional story, but instead a documentary of a real-life event, then a focus on that kind of minutiae would perhaps be a key element of the narrative. But The Martian is first and foremost a character drama using Mars as a setting.