Disabling redirects

Hi and thanks for the great plugin. I use it since many years and now I have an important question.

I just used this code to disable the redirect function, since one plugin I worked with was affected by custom permalinks.

function yasglobal_avoid_redirect( $permalink )
{
return true;
}
add_filter( ‘custom_permalinks_avoid_redirect’, ‘yasglobal_avoid_redirect’ );

Now everything works. However my question is: What does it do exactly? I have 25000 URLs on my page – will the existing permalinks be affected from now on? That would be the worst case.

Otherwise I would really be glad if you quickly explained what this code does and how it affects my page (old and future pages).

Thanks a lot