Personally I think it'd be a shame being afraid to play efficiently because someone who has no idea how the game works might scorn you. When I've played DNC in DR sometimes I've even switched mid-pull from the dps over to the tank or healer because they're using Essences and Actions and doing far more damage. If the dps or anyone in my group scorned me, I'd explain, point to the enmity meter and stick with what I was doing. I'd never choose to play badly out of fear of ridicule. Similarly I've had some great DNC's who have switched over from dps to my WHM and AST's who treated me like a favorite child with their cards, which only helps the run.
DNC's in particular fall into 2 categories. The DNC who looks at every factor from gear, dps, uptime and chooses their dance partner carefully and the DNC who follows the Balance priority list even if their partner dies 6 times and is 50ilv lower than the rest of the group. DR in particular is designed to encourage thinking outside the traditional boundaries of tank, healer, dps and set rules. A dps could become an amazing healer or a healer the best dps in the raid.
I think most know, they just aren't bothered farming one. Ideally Castrum and DR would drop significantly more fragments and we'd have bonus rewards in DR based on passing a certain moderate damage threshold. I don't understand why developers never consider rewarding players for playing well and being innovative. Instead it's punishment such as mettle loss, and taxes such as fragment grind/purchase. No wonder players aren't motivated.