Limit Break Dancing
Yep, like I said: it seems like a lot on paper, but didn't seem like that much of a difference in practice.DM: You have 65% of jumping over the chasm or fall to your death.
Players: 'No problemo, as long as I have 50% I'm good. I don't need the extra 15%.'
DM: (perplexed) 'So be it. You have 50% then.'
As his character is falling to his death the player admits he would have like to have the extra 15%.
Numbers matter in a RPG. 15% is the equivalent of a +3 weapon. It matters a lot in the context of the adventure.