I am not saying, there is anything wrong, about learning & reading books, as that is not my point, at all. What I'm saying, is there are people that make decisions, about what plant, gets classified & how & with which others & then they may actually have never even seen or grown that plant, at all, ever. Yet, make major decisions on classification, by getting a "consensus" & taking a "vote' about it & then suddenly it's all different & we no longer even know what name our plants even may be called ,any more !
Learning by reading is very important & being able to remember it all, is , very important too...You don't always learn by books alone & it may take years, to understand complexities of plants & their biology & vasculature, even from pollination, to forming a viable seed , to being able to germinate it & grow it & how it became fertilized, in the first place & then eventually to mature growth & flowering..Then, there's genetics & all sorts of things that some are even studied, like some ,we may know about nearly their entire genetics., these days..That, is how they ought to be trying to classify plants ! Not some "vote'"or "consensus" but to consider genetics, in the decision making process of classification of plants & how distantly, or closely related, they actually are.. Including chromosome count, & such..I think they have "difficulty" with just figuring out, where some may have originated. So they try to "guess"!
There was once, a rather rapid, "explosion" of flowering plants almost suddenly appearing, considering it happened over a fairly quick, or brief span of time,compared to 'geologic" time, (Compared, to the age of the earth...) & now, they 'think" time existed before some "scientific -big ,bang-" & haven't even solved that, "riddle' yet..