Boris,
Due to the position of the kickstart pivot brackets welded to the crossmember under the gearbox, the excessive strain put on it when kickstarted has been known to break the crossmember welds to the frame. The giveaways are when on the centrestand the bike leans to one side or both tyres touch the floor.
Being realistic, I think it depends on how heavy you are and how you kickstart it. Unless you're one of these 20 stone blokes who feel the need to jump on the kickstart from a great height then I wouldn't worry. The engine turns over quite easily without the need to apply excessive weight from the sky. On my previous OIF Thunderbolt, it would start with a gentle prod -most of the time.
Hope this helps
Chris