Sure, but it doesn't make sense that six individuals leveling up at 5% greater speed would mean that the group levels up at 30% greater speed.
Sure, but let me just try to explain myself one last time because I think you're calculating an incorrect - but similar - percentage. With this scenario, assume that every character is a clone of the party leader, which means same class, stats, etc.
There is a party of six people.
They enter a fight and win 100 exp each.
Since they have +5 wisdom, they each get 105 exp.
That's 105 exp a piece, which is 105% of what each person would have gotten.
That means they all leveled up 5% faster than normal.
Each person has only gained 105% of what they would have gained, therefore they are leveling at 105% efficiency. That's 5% faster leveling for not only each person, but the group as a whole as well. If you take away one person, the party would still level up at 105% total efficiency. If everyone in the party is leveling up 5% faster, the whole party's leveling speed can not exceed 5%. What (I think) you are calculating is the combined experience provided by wisdom without looking at the total experience gain, so it pretty much looks like this:
5 wisdom each
5% x 6 = 30%
Add this to the mutual experience (party's normal total exp percentage)
30% + 100% = 130% leveling efficiency
This is wrong because it's looking at the party's exp percentage without considering that there are six characters who earn it and split it. Let's look back at the scenario again. We've established that all six characters are leveling up at 105% efficiency; 5% faster than normal. Six characters leveling at 105% of their normal speed is 630% of what one person would receive
. The number 30 is only 5% of 600. Since 6 characters in a group provide a combined 600% exp, and we're adding 30% to it, then that also must mean that the leveling speed has been combined to form the extra 30%. The math should look like this:
Six characters get 105% experience
105% x 6 = 630% of what one person gets
600 / 30 = 20 (20 x 5 = 100, therefore 30 is 5% of 600)
If what you're saying were true and we could get enough people working on this all at once (to the point where the leveling speed is in the thousands, so like 34 groups but whatever), you would theoretically be able to level up anyone immediately. The only reason I press the subject this much is because if people see a big "30% faster level rate for our guild" up there it might get their hopes a little too high, you know?