In Lesson 10.6, is the example Tu peux me tutoyer ! in which the translation is given as You can say « tu » to me! The English translation is grammatically incorrect; it should read You may say « tu » to me!.
Can speaks of a person's ability to do something, but may, gives (or asks) permission to do something. There's a distinct difference between can and may in English.
Pouvoir in the example, gives permission and isn't speaking of the listener's capability. Is pouvoir, therefore, one of those words that has multiple meanings in English?
Post note: The example Vous pouvez me tutoyer si vous voulez ! has the same translation problem.