Ahsan Allahu Ilaykum Sheikh, my brother in law is, subhanallah, a Hafiz but he has little knowledge. If in future a case comes were we cannot find a Masjid for Juma´ah, could he then read a Khutbah from a piece of paper since he must lead the prayer, because we memorized less than him.

Ustadh AbdulAziz al-Haqqan

The one giving the sermon doesn't have to be the Imam who leads the salah.