Please just don't call Fill if you can't support.
If you're no good at skillshots, don't pick Thresh. If you're prone to being over-aggressive, don't pick bot lane. You ally needs to be completely in sync with you for that to work.
Totally agree. But really, you should try to learn all of the roles before heading into ranked queues anyway. There's a reason people hate playing particular roles (coughs support coughs coughs) and it's because they simply don't know how to play them. Try to understand the fundamentals of a role before taking it into ranked.
