i've done mdma 4 days in a row before, it was pure mdma from the same batch and each day had increased dosages with lessened effects. the 1st day was incredible with 300mg. the 2nd day was still a good roll, dialed pupils and feeling incredible with 200mg. the 3rd roll was really weak, hardly any euphoria and more of a weird cloudy high, dosed with 400mg. the 4th roll was nonexistent, my pupils didn't even dilate and hunger didn't go away with 300mg, just a less euphoric weird type of high. relaxing but weird. probably would've taken a lot more to achieve an actual 'roll', tolerance seems to jump up really fast. i stopped altogether for 2 months and rolled again with 150mg and rolled just fine, then continued taking a break for a few months so that i can keep the magic.
so i would imagine that 4 day marathon would be an example of what happens with more long-term examples like yours. if you roll fairly often for the better part of a year or whatever, then you may be doing to yourself like what i did to myself, just over a longer period of time. back in the early 2000's ii used to do it every weekend and tolerance went up, ended up eventually having to take a break for over a year then rolled again for the first time in over a year and it was incredible. take a break, the longer the better and the magic always comes back in my case.