Here I encountered the following sentence:
However, most people understand their side is good and the opposing side is bad, so it’s much easier for them to form these emotional opinions of political parties.
This sentence features a misuse of 'understand.' 'Understand' is a verb of success. If you understand something, then it is the case. For example, if you understand that both 2 and -2 are square roots of 4, then this is the case. Otherwise there is a failure to understand. 'Understand' in this respect is like 'know' and unlike 'believe' or 'think'. My knowing that p entails that p is true. My believing or thinking that p does not entail that p is true. My understanding that my side is good entails that it is. The above sentence should read as follows:
However, most people THINK their side is good and the opposing side is bad, so it’s much easier for them to form these emotional opinions of political parties.
Not necessarily, says Taubes, who suggests that the ad hoc societal test of the low-carb solution lacks certainty. “If you understand beyond a shadow of a doubt that your disease is caused by sugar and flour and refined carbohydrates,” he says, “you are more likely to adhere to a diet that cuts them out.”
Some will say that usage changes, to which I will reply: no doubt, but not all change is change for the better.
Call me a prescriptivist if you like, but don't confuse me with a school-marm prescriptivist. If you end a sentence with a preposition, I won't draw my weapon. For that is a piece of pedantry up with which I shall not put!