I'll be playing DK regardless of what mages/rogues are doing and there will be fights where I can be #1 if played perfectly and there will be fights where I can't be #1 even if played perfectly and that is fine because nobody should be entitled to that #1 spot 100% of the time. Even if every class was numerically identical you will still have someone at the top of the meters due to multiple variables such as RNG, uptime, activity, rotational accuracy, lag, gear and so on. Not to mention "weaker" classes will still be used for their utility.