Just outright trialing like that doesn't work for most high end guilds for a few reasons. The biggest being that they might have to sit someone out to trial you, and without any idea of how you will perform, this could lead to problems, and a waste of time. If you are trying to fill slots in a roster in a progression guild, you don't want it taking more time than necessary.

A world of logs report will be asked for by most guilds who are clearing hard modes right now. It allows them to check not only your dps, but it can give a good idea of your rotation, what killed you when you died (Did you stand in fire? Was it avoidable?) and up-time of certain abilities. (eg: A holy pally with a low up-time on their judgments might raise a flag)

A parse gives the guild a rough idea of how you perform BEFORE they commit to having you in their group. It makes them feel more like they're trialing you and less like they're potentially going to have to carry you.

As far as you talking about keybindings, this is often why they ask for a ui screenshot. They're checking to see that you have the required mods and that important abilities are keybound. Argue all you want, but keybinding is and will always be faster than clicking.

And last, because it cannot be stressed enough, spell check your app! Spelling and grammar may not seem important but if you can't take the time to run your app through a spell check, the guild isn't going to want to take the time to read it.