You can do something similar with the 2x2 rib too. On the first dec round, k2, p2tog, k2, p2, repeat. On the next dec round p2tog on the p2s you skipped the first time around; then do the same to the k2s on the next dec round - k2tog, p1, k2, p1, repeat and finally k2tog on the last dec round. Or you can alternate the p2tog with the k2tog every other round.
sue- knitting heretic