adding to the OP's: Ghazal is the romanization of the word غَزَل in Arabic, it almost means "flirting", and is a form of Poetry that dates to the Pre-Islamic time, usually a poem about love and romance.
The author seems to stress about the rules of "Ghazal" (and there is a lot more to it than just couplets rhyming the same) but these are just general poetic rules the Arabic poets used to adopt, and not exclusive to romantic poetry aka "Ghazal".
The author seems to stress about the rules of "Ghazal" (and there is a lot more to it than just couplets rhyming the same) but these are just general poetic rules the Arabic poets used to adopt, and not exclusive to romantic poetry aka "Ghazal".