While tossing in the asinine requirements I want to avoid. You know as well as I do what happens once you toss in level correction into the mix, and I for one don't want to see a system that once again favors stat stacking to ridiculous levels to overcome level correction. Moreso for accuracy, which was king in FFXI for a good part of the game's life yet was stupidly rare in gear in the necessary amounts to effectively overcome level correction.
Only when time is at stake, and only when forced partying comes into play. All you're giving way to is the crap from XI repeating itself, so I can't really support that because it only creates that gap between the haves and the have nots.People will always use the most effective method for gaining SP/EXP (currently it is Leve abandoning), that will never change and removing the cap will make no difference in that respect all it will do is allow people to have more options in gaining that best SP/EXP per hour and give people a reason to make full parties and go out and fight tougher Mobs.
I don't even need to go into how this affected jobs that had "sub-optimal" set ups and were "sub-optimal" choices for exp parties. Overcamping led to greater resource consumption in parties, which led to people starting to try to work around downtime to continue maximizing exp/hour, which led to making anyone who has downtime built in to the job (read: black mage) into a liability barring specific conditions, which led to ousting of jobs, which also had a hand in screwing over hybrids (read: Red Mage). All because people had big number syndrome and wanted to see 200 exp from a dead mob. The current cap curbs that, nipping the problem in the bud.
You want full parties, go do the high level raids. Just keep that stuff away from the leveling process.
At least quests give you some sort of story behind things. Grinding in one spot and killing crap over and over again doesn't. That's called "making the grind bearable to a normal person rather than turn it into a chore that would bore a normal person to tears".