I really prefer Choice Scarf, Specs, or Life Orb on Palkia due to how Ubers is metagame wise. Bluffing could only work to a point because if the person knows their damage calcs, they could tell if it is Choiced or not. Being able to hit Lugia harder can make a difference on beating it. Not factoring in Stealth Rock, variations of Palkia without anything to boost Thunder's damage have a very low chance to 2HKO the standard wall Lugia set assuming Lugia doesn't Roost off the damage. By having Life Orb equiped it always will 2HKO wall Lugia if it doesn't Roost off the damage. Lugia is quite a tank to beat otherwise which is part of why I prefer a bit extra power on Palkia. The Choice Specs Palkia set actually has a fair chance to OHKO Wall Lugia after SR. The damage it can deal is 72.1% - 85.1%.
Choice Scarf is basically just a Revenge Killer set. It can come in handy at times, but it is able to get walled more easily.
Choice Scarf is basically just a Revenge Killer set. It can come in handy at times, but it is able to get walled more easily.