I don't think anyone has a scientifically based answer. Long term, low dose exposure or short duration, high dose exposure. I wouldn't call 100 mg/week a "low" dose, either, but I'm not a fan of tren to begin with and that's also something everyone has an opinion on.
The way I choose to think about it: if you're running a cycle, you have to be on point with your training, nutrition, sleep, and side management. If not, you're exposing your body to a bunch of stress and potential damage that you're not going to take advantage of... it's a waste of your organs. So the question is, can you stay fully dialed in for as long as you're going to run low dose tren? Are you sure that work, health, your kids, etc... nothing is going to come up that's going to get in the way of a week's worth of training?
There is something to be said for people who blast the fuck out of compounds for short periods. If you're gonna accrue that much exposure, you ought to ensure that you're maximizing the effect of each mg. The answer may have more to do with how predictable your life is and how you can manage the drugs than anything else.