I'm not very experienced in electronics, but I'm becoming somewhat of an aged fella; experienced in life. One of the very few things that has been constant in my life is the general lack of correctness in "well known" things like this.
That is, the more people who "know" something, the less likely it will ever be verified. Knowledge that is taken for granted is never verified. Why would you test it, when everyone "knows" it?
Everyone "knows" that XML is far slower to read, write, and parse than plain text. (false.) Everyone "knows" that HTTPS is far slower than HTTP. (false) All sailors "know" that a snapped deck line under tension will cut you in half if it hits you. (false.)
I suspect this is one of those things that everyone (or almost everyone) takes for granted and never verifies, trusting the (potentially false) community wisdom over the scientific process that could prove it one way or another.
The hallmark of this phenomena is the 100% conviction shown in something that is a potential pain to test. In software development, false community knowledge is rampant.
I'd bet that few of you who declared the 90 degree corners a bad idea have access to the RF signal generators, RF leakage detectors, or any of the necessary equipment (whatever that equipment may be) to test this, and those of you that do have access to this equipment wouldn't use it to test something "well known" like this.
I'm not arguing with anyone. I can't tell you that any of you are correct or incorrect, because I don't know who is correct here, but I can say that this REEKS of generational knowledge that has never been tested by anyone repeating it today, and that has just as much of a chance to be correct as it does to be incorrect.