How many jobs can you decently gear up?

[dspguy]

If you want to do the "best DPS" and be the "best player you can be" (DPS-wise), then it is a combination of BiS gear and executing your rotation at the highest level. The latter you can work on with any iLvl gear. The former required raiding (initially) or now the 24-man weekly token and/or hunt marks (minus the weapon). There is a marked difference between a BiS player performing at the highest level and someone with i620 gear. However, the necessity for BiS gear is fairly limited.

[Gemina]

There is a marked difference between a BiS player performing at the highest level and someone with i620 gear. However, the necessity for BiS gear is fairly limited.

Well, of course there is. That goes without saying. A better correlation would be a player in i620 gear performing optimally vs a player on the same job in BiS performing suboptimal. ilv requirements to enter a duty are typically much less than the requirement set by the players themselves. They can do this in hopes to reduce the pool of incompetent players, but they will also cut out a portion of players who are perfectly capable of holding their own weight as well. The necessity of BiS is determined by the party leader, not the game.