Originally Posted by Kiwi Flyer

That penalty is before taking any flights.

If flown any sectors, then the equivalent one way fare is calculated for the sectors flown and added up. This is subtracted from paid fare to determine the refund. Thus refunds are not likely to be significant if the RTW was purchased cheaply compared with one-way fares for the sectors flown. There is no easy way for passengers to calculate/estimate the refund.