Fignon was a genius. When Massen attacked on the flat between Cipressa and Poggio, he knew it was the moment. But PDM had 5 - 6 guys up there. How could they let Fignon slip away? A mystery.
I agree...and you probably know this as well but Fignon said of the 1989 win, that he could not attack again on the Poccio like in 1988 as he would be heavily marked by the others - so he had to attack elsewhere. He chose somewhere between Cipressa and Poggio like you said. He said he felt good, and when Maassen (who was on good form) attacked between Cipressa and Poggio (at 14:07...) he decided to join him (...15:04) . He said at the foot of the Poccio they both had a 40 seconds lead, then Fignon pushed hard on the climb, dropped Maassen (23:16...) and won solo.