Conversely, I didn't even have to even click in to understand it hah. Been playing AoE for around 20 years.
I was confused as well, because I just had chatted with someone about whether the aoe2 monk conversion ability on certain buildings was hardcoded or not (they can't convert i.e. Town Centers, Monasteries) ... turns out it at least used to be, no idea about now.
Likewise, I thought it was something to do with blood pressure :)