Yes, it is true and I took ample advantage of it during my time there. Every semester after my 1st year (I was a better student in the beginning), I would resolve to attend classes and would manage to do so for the first 1–2 weeks and then just give up. I rarely attended classes after that. The exception to this were the labs (for obvious reasons) and some physics classes which I truly loved and enjoyed (e.g. I never missed R. R. Mishra’s classes).
Some professors used to have surprise tests during lectures and part of the risk of missing classes is missing those tests. We tried to combat this by getting some of our more studious friends to text us the moment they saw questions papers in the hands of the profs and we would then rush to class. The profs aren’t stupid so this strategy very rarely worked. They wouldn’t let us take the test (totally reasonable of course!) and we would have to sit through the lecture anyway! As a consequence, I would essentially miss a small chunk of my final grade and had to rely solely on the midsem and final exams (which I would study for the night before with all my friends)