Yes its true,
Consider disabling AutoEventWireup for your application.
Setting the AutoEventWireup attribute to false in the Machine.config file means that the page will not match method names to events and hook them up (for example, Page_Load).
If page developers want to use these events, they will need to override the methods in the base class (for example, they will need to override Page.OnLoad for the page load event instead of using a Page_Load method).
If you disable AutoEventWireup, your pages will get a slight performance boost by leaving the event wiring to the page author instead of performing it automatically.