i think the powers itachi gave naruto must be some cool jutsus.
The reason for my thinking is this;there was a time jiraya was explaining stuffs about akatsuki to kakashi,telling kakashi that akatsuki members move about in a two man cell for espionage reasons and gathering or assembling of jutsus.[chapt. 143,pg 6,bottom panel]
from this,some part of me thinks itachi passed down the jutsus he gather over the years.(his jutsus before akatsuki and jutsus he gather as an akatsuki member).