Im not going tomorrow. To all of those who are spending a fair bit of their money to travel to London and watch the match, sing what you want. Who is anyone else to dictate how you should behave.
At the end of the day, we're all Saints fans, and want what we think is best for the club. Whether you think it's best we win tomorrow, or lose in the hope that the manager gets the boot, is entirely your opinion. In my book it doesn't make you any better or worse as a supporter.