I would have to agree with Thevedis, if you have given time to fully cool-down since your last session I do believe 60 nodes is a bit of an exaggeration. It also could be "fatigue" is different to different people. I mean are you considering fatigue as in, the first time you damage 1 item? Because you can gather quite a bit longer and still harvest/mine/fish at about a 80% rate w/o damaging items....until it gets really bad.

Also, if you are intent on working towards those achievements and that is your sole motivation for doing the gathering, then the fact that your in fatigue shouldn't matter since damage chops still count towards your counter.