PuzzleRocks - DS used to have days where he ate loads and days where he ate almost nothing. The mantra for BLW is 'Food is for fun, until they're one' meaning that as long as they're still having their milk (bm or formula) then it doesn't matter how much solids they eat. Breast milk has more calories, per weight, than any solid food anyway.
The idea with weaning is that by the time they're 12 months, they should be on three meals a day, but some children take longer to get there than others, and BLW means they can go at their own pace.
DS didn't eat decent amounts of solid food consistently until he was about 10 months. No child will voluntarily starve themselves, apparently, although I did have days where I was in despair because he'd eaten one bite of carrot all day! Our saving grace (in terms of my sanity, not his health - he knew exactly what he was doing....) was breakfast - he loved Weetabix from early on so always ate that, and tonnes of yogurt.
We did it initially because DS point blank refused to be fed with a spoon, he would just seal up his mouth tight shut - apparently BLW is more intuitive for a bf baby because they're used to being in charge of how much they eat, iyswim. DS was certainly in charge.....
I have to say I can heartily recommend it, it was really fun although very messy, and DS is now a fantastic eater, no strange fads, he eats everything and is completely in charge of his portions - when he's full, he's full, and he just stops eating. And he's a happy, lively nearly 3 year old.