The initial part of this article sounded a bit handwavy to me: "Evolution could have simply tweaked the parameters of sperm development so the ideal temperature of its enzymatic and cellular processes was the same as the rest of the body’s processes. [...] The fact is that there is no good reason that sperm development has to work best at lower temperatures."

Do we understand enough of the sperm development process to be able to affirm that a higher temperature variant of the process could work better, and that the only reason for the lower temperature one to have won is path dependence?