A Blood Elf walks into an LFR Underhold.
The trash and first boss are executed perfectly, first pull with no deaths, as is all the trash up to the Spoils. The top dps is a Warlock, who declares as groups are being sorted he'd like to go afk because 'this bos (sp) takes too long.' When called out on this by several members of the party he links both Heroic Spoils and Heroic Garrosh, and tells us all to suck it. When challenged to the fact he could also have been carried through both of those fights, his response is simple.
'You're just jealous I'm better than you.'
The Blood Elf then replies 'You should be grateful you can heroic raid to begin with. Some people just aren't that lucky.'
There is a silence, and the fight begins.
The Warlock is also top dps in this fight.
Sometimes, it pays to remember you aren't the only person who needs to LFR.
You should try and remember that some people don't have the opportunities you do, and that being good at something doesn't necessarily mean you're the best, it could come down to having the time. Gear isn't a badge of honour, it's just a means to an end. Achievements aren't the way to show how capable you are, it's when you pull your weight with everyone else and make sure the Group succeeds, because you can't get a 25 man achievement on your own.
When you really want to be taken seriously, sticking your abilities into someone's face is likely to have the opposite reaction to the one you're hoping for.
Respecting everyone should not be an afterthought, if you choose to enter LFR you should do so understanding what is expected of you and not to slack, or give anything less than your best. Laughing at those for whom this is their only way to see content isn't just mean, it is cheap and easy, and if you think this is acceptable it is time for a long, hard think about why you play with other people to begin with.
If you wish to prove how good a player you are, grasp you need to give back and don't just keep taking.
Learning to play does not mean generating the largest numbers.