Canadian here, and yes, it's basically impossible to mark your ballot wrong for a commonwealth parliamentary election for the simple reason you only vote for a

Canadian here, and yes, it's basically impossible to mark your ballot wrong for a commonwealth parliamentary election for the simple reason you only vote for a single thing: who should be member of parliament for your riding. Since there is only a single question there is tons of whitespace between options and you can't accidentally mark selections for one question in the space asking a different one. I've never had to vote in a referendum like brexit, but it wouldn't surprise me to learn the ballot was more complex that the usual parliamentary election one. Looking at images of the brexit ballot it appears pretty similar to what I'm used to, but with far less white space between options.