It's always interesting to me just what I find in the answers I receive from best men around the world. You can easily see that a lot of friendships are forged from the ashes of a good punch up when you were about 5 years old and the groom took a dislike to your sandals, or more commonly, when asked in what ways has the groom helped you out - the answer is invariably: he hasn't. From brothers, to best friends, we have interesting relationships with the groom, and the questions I ask, provoke a lot of memories, and many times those memories are not about the groom.
I lose count of the number of times I'm sent stories about the groom, which merely involve the groom being there. The best man was the beginning, the middle and the punchline. The best man speech is never about the best man, and if you keep that in mind it will prevent all sorts of awkwardness. Firstly the boring cliche of talking about how you felt when he asked you to be best man. Who cares? You've got a talking time of about 7 minutes, fill up with dull, meaningless stuff like this, and soon all you'll have left is enough time to wish the happy coupe all the best, or even worse turn your speech inot a 45 minutes lecture.
The problem is many people love to talk about themselves, and it doesn't matter to them if the story isn't about the groom, if they think it's a belter and it will raise their stock, then they're sticking it in. Big mistake. It will soon become apparent that using this speech as a vehicle for self aggrandisement, and nothing is more tiresome and pointless.
So, look at what you've written and see how much your pointing the spotlight at yourself. Once is too many; more than once is unforgivable.