i agree hatton won't go straight to #1, but i don't see what margo and cotto fighting each other will have to do with anything. if margo wins again, it will stay the same, and depending on cotto's performance he could drop further, and if cotto wins he will only be doing what he was expected to do before fighting margo, and may take margo's place, i couldn't see cotto moving higher than 6 even after beating margo.
Margarito got Cotto's P4P position without even being on the list before. Pavlik got Taylor's position without being close to a top25 P4P list back then. And Margarito and Pavlik didn't debut somewhere around 10 to 15, they recieved the position of the fighter they had defeated. Hatton is already a P4P-er, only missed out a couple of month on the P4P list after the Mayweather loss (yet Cotto, who got beat more badly, is STILL a P4P-er despite never beating ONE P4P-er, over the hill Mosley was the closest, but that's it. Over the hill Tszyu and over the hill Castillo were both P4P-ers when Ricky fought them). You see it's either constantly beating top opposition to get on the list (Cotto), or beating a guy at high position to get his P4P ranking (Margarito). Hatton did both: Tszyu, Maussa, Collazo, Urango and Malignaggi were all champions, Tszyu and Castillo were P4P-ers, and Ricky's only loss it to then-P4P best Mayweather. Vs. Pacquiao, who fought at WW last time and his fight night weight was a typical LWW's fight night weight, in my view Hatton is going for the P4P top position. But don't be in shock if Pacquiao will be the betting favourite.