[tei-council] rng:group but no rng:choice

I just stumbled across the content model of climate (and there are more …) which looks like <content> rng:group rng:zeroOrMore rng:choice rng:group rng:oneOrMore rng:group rng:oneOrMore rng:zeroOrMore rng:choice rng:zeroOrMore </content> My question is: is there some magic to the surrounding rng:group or could that be deleted? (I don’t intend to do so but was just wondering …) Best Peter