You said: Also SD+3 moves run life orb no weakness policy and no HP investment
I don't think you're right. I've seen many people run SD+weakness policy just to give their aegislash a huge attack boost and then to sweep and cripple many pokemon
Yeah... lower on the ladder...
+6 252 Atk Aegislash-Blade Shadow Sneak vs. 252 HP / 232+ Def Skarmory: 168-198 (50.2 - 59.2%) -- guaranteed 2HKO
^Can still roost/phaze
+6 252 Atk Aegislash-Blade Shadow Sneak vs. 0 HP / 4 Def Mega Pinsir: 247-292 (91.1 - 107.7%) --
50% chance to OHKO
^Can EQ or even just go for return. If this wasn't a gimmicky stance dance set like your using life orb would be the KO. Also a +0 ice beam or t-bolt from almost anything would kill this rather than having to go all the way up to +6.. looks totally overpowered.
Weakness policy sets prebank was KS+SD+shadow sneak and a pick between shadow ball for no coverage, sacred sword for coverage, or iron head for stab.
Or they used weakness policy and ran KS+Autotomize+2 coverage moves which was easily to take down since scarfers still outspeed and it relied on being left half dead with weakness policy to deal respectable damage..