Exactly. HTML has structure. It is not the same as flat text, although you can flatten and edit it as such.
As an example sentence, take the following:
"The French equivalent for the English "Good Evening!" is "Bonsoir!", whereas Italians might say "Buonasera!" to one another for similar effect."
There are four languages in that sentence, two of which are English. You may need three editors to deal with them, or you can flatten the sentence and simply edit everything assuming you knew all three.
As an example sentence, take the following:
"The French equivalent for the English "Good Evening!" is "Bonsoir!", whereas Italians might say "Buonasera!" to one another for similar effect."
There are four languages in that sentence, two of which are English. You may need three editors to deal with them, or you can flatten the sentence and simply edit everything assuming you knew all three.