Forget batting, we all know Pakistan's historical weakness against bounce, similar to how swing in England has historically bamboozled most Indian batting lineups.
Even among bowlers I have seen Pakistani greats like Waqar, Shoaib, Gul, Amir lose their minds in Australia. They see steep bounce, their eyes light up and they just lose the plot when it comes to finding the correct line and length especially length. Shoaib wasted an entire spell bowling a ferocious short pitched barrage against Ponting in WACA 20 years ago, what happened? Looked good but Ponting scored 198 and Australia won by an innings. Similarly Wahab bowled a ferocious spell in the 2015 WC QF and made Watson look like a rabbit, but he overdid that and Aussies won comfortably with 15 overs to spare, you can't win a match just with bouncer barrage in Australia, must mix the short ones with fuller ones, play with the lengths etc. Far inferior Indian bowlers like Mohit Sharma, Praveen Kumar, Ishant, Natarajan etc. have found more success in Australia than Pakistani greats because they didn't get carried away with the bounce, found much better lengths to mess with the minds of opponent batsmen.
There is an assumption here that Shaheen and Naseem will be too hot to handle on 23rd but from what I remember from their previous tour they got tonked by the Aussies, a year later the likes of debutant Siraj, Thakur, Natarajan restricted Australia to low scores consistently. I know it is a different format but what I mean to say is that length is very important in Australia, miss it by a few inches and the bowlers will get carted around. There is no guarantee that Naseem-Shaheen will find the prefect lengths especially after coming back from injury, and if they don't find that they are going to bleed runs. Naseem with his short height can't afford to miss his lengths by an inch otherwise he is cannon fodder in those conditions. I think PPers will be in for a surprise on 23rd, Indian trundlers are going to surprise many.