Aitch, that blog is a godsend.
Had a look, and will give it some serious thought over holidays....tbh, I didn't start off with BLW 'properly' until dd was about 7 months, she seemed ok at 6 months with babyrice and a few mouthfulls of mush. Its when it never progressed beyond that, then she started refusing the spoon altogether and losing weight, that I re-thought.
But bearing that in mind, I would say that to some extent it will depend on the baby - my dd is on Ranitidine and Domperidone: meds will deal with a great deal of symptoms, so those who ARE on meds can probaby cope with normal BLW unless their reflux is v extreme. Those who aren't, probably need to manage their symptoms through diet and other ways - much as adults do, before they resort to Gaviscon/Zantac etc. Which would mean, as that Mum says, bland, non-acidy foods.
If a baby's oesophagus is so sore from acid it can't cope with lumps, tbh, I'd want them to be on meds. But otherwise, definitely liquid is easier than lumps!
My own dd has an extra issue, laryngomalacia - floppy larynx - which has given her problems with breathing in the past (especially when she got RSV bronchiolitis at 4 weeks) and which can interfere with feeding, because its hard to breathe and eat/drink at the same time. Most babies with floppy larynx also have reflux - and reflux makes their tubes swell up, which then makes it harder to breathe: so managing it is extra important.
She's also got moderate eczema, so am being slightly careful with foods from that angle. We've been referred in case dd's swallowing was held back by the laryngomalacia, but since starting BLW she's actually doing fine - haven't weighed her recently, but can tell by the sleep and the plumping up
Not sure if any of that helps - but will watch and learn (in jacket, hose handy) over next few weeks and report back.