Stay on message to win buy in

I read an interesting blog post by John Kotter. John makes an interesting point about the nit picking, expert and sceptic who tries to de-rail the presentation. His key message is "Stay on message. Don't delve too deeply into single attacks. Don't forget about your broader audience."
http://blogs.hbr.org/kotter/2011/01/stay-on-message-to-win-buy-in.html

This is great advice and I'd also like to add:

• Polish your shoes! Great meeting performance is all about attention to detail and preparation. By suitably pre-positioning your stakeholders and doing your homework you should be able to identify these nit pickers before the meeting. This gives you the option to use their enthusiasm, passion and knowledge to your advantage. You may even give them the stage to get them onside.
• If despite your great planning you are faced with the 'expert' don't push back against them, don't get into a debate with them. Recognise their expertise offer to take it off line and as John Kotter says focus on your key message.

Although my key message is do your homework!