You have to hold it a lot tighter (un-naturally) to get this to happen.
I have not noticed anything different to my previous mouse, but that could be just me. Tricky one to say about this and hopefully someone else might be able to comment on this.
Update: I had the time to view that video on the issue and if I press very hard on the side wall under the buttons, it does indeed click. However, the amount of force I used is far grater then I use on the buttons, so that would explain why I have not noticed it in use or gaming.
If you really press hard on the buttons with large hands, I can see the potential for an issue, but I think this might be an issue with manufacture tolerance on the wall plastic thickness and possibly some thinner ones slipped through QC.
Its not putting me off for my personal use.