The British singer exchanged vows with Giovanna Falcone at London's One Marylebone venue last May (12), and in the run-up to the ceremony Fletcher battled extreme nerves about his groom's speech.
He instead wrote his words to the tune of several of the band's hit songs, including All About You and The Heart Never Lies, to entertain his guests.
Fletcher shared a video of the 14-minute verse with his Twitter.com followers on Sunday (06Jan13), and at the beginning of the clip the star explains his reasons for the unusual speech.
He tells guests, "I absolutely hate public speaking. Me and public speaking are just not compatible, we don't go together very well at all.
"Mainly because I don't have any idea how to write a good speech but I do know how to write a song, so I hope this isn't cheating my way out of it too much."
To the tune of the band's track Obviously, the star is seen singing, "We are so grateful to so many people/ But we're saying thank you to only a few - I'm sorry. So if I don't thank you, it means that I probably just forgot you/ But obviously that doesn't mean that we are not grateful... it's just I'm forgetful."