Haha
The song is tongue in cheek and the fact it's wound you up seems to suggest it's getting the reaction intended.
The red part of Liverpool detestd United simply because they can't stomach the success we've achieved.
Also i'm not sure if you've noticed but the bulk of the hype built up around the Ryan Giggs issue has died down massively and SAF has helped that with two simple yet well thought out actions. Announcing the De Gea signing and making the press conference about him rather than Giggs - You mustn't forget the 'idiot' as you put is so eliquently knows excatly what he is doing and it's part of the reason the club have been so successfull.
You support Barca on Saturday all you want, won't help make up for the fact your team are away on their holidays right now rather than playing in the biggest club game of the year.
Scouse bitterness and jealousy never ceases to amaze.
Manchester United - hated, adored, never ignored.
Enjoy the match