Time limit to re-enter dungeons

[Richard]

The reason they NEED a 5 minute refresh timer is because these 2 new Dungeons are slated to become a new source of group SP. We're losing the benefit to grouping up and running Leves as a group, so to ease the loss of Leve-Linking, The team has given us dungeons we can run through for a constant source of good SP. No fighting for other groups for hunting grounds. No r50s running around farming SP mobs.

How is this a bad thing?

it may be an indirect form of XP but the mobs in the dungeon are Lv60 and if you watch the video the team was getting like 162 SP per mob. Yoshida already said they are focusing on making true leveling a more "field grind" oriented experience along with quests for parties.