Help me understand Safemoon's _getCurrentSupply() function

I've been reading through Safemoon's contract and things made sense to me until I got to this function. In particular, this line:

if (_rOwned[_excluded[i]] > rSupply || _tOwned[_excluded[i]] > tSupply) return (_rTotal, _tTotal);

When would _rOwned[_excluded[i]] ever be greater than rSupply? Better yet, when would _tOwned[_excluded[i]] ever be greater than tSupply? Isn't tSupply the maximum token amount for ALL holders?

This line also doesn't quite make sense to me:

if (rSupply < _rTotal.div(_tTotal)) return (_rTotal, _tTotal);

Would appreciate it if someone could help me understand. Thanks!