Against my better judgment, I have a couple things to say.
15% is not "too restrictive". I eat that easily, on a wonderfully healthy diet of fresh produce, lean protein, and whole grains, which is how everyone should eat. Mind you, my 15% is more of a daily guideline than a per-meal, and I do occasionally splurge. But I don't eat junk, and I certainly don't eat crap with mystery ingredients from restaurants (and yes, I DO eat out, actually). You do not need to have that stuff in your diet, and it's really super freaking easy to avoid it.
I am stable and have been for two years so far, so obviously I'm doing SOMETHING right.
Also, 31.5% is not "barely" more than 25%. I'm not normally one to argue semantics, but in the world of IBS, 6.5% is a BIG difference.
Since you already have what you consider to be a "safe" fat percentage range for yourself, and you've done the math, and it falls within your range, I'm guessing that what you really want is for people to tell you to eat it. So, I recant my previous answer... go ahead and eat it. Knock yourself out.