I'm so curious to see what other say! There was a post last week about blow outs...my LO has very hard BMs...practically like an adult. There's no way he could have a blow out. He's breastfed and get three solid oatmeal/whole grain purees a day...I wonder if its the type of solids that determines blowouts, etc?
If you're concerned, maybe try a different solid for a bit? I believe oatmeal causes "harder" BMs than rice. At least, that's what I've heard...