Cheesy feet - SDs do need to be in groups, they are shoaling fish like tetras, and are also very nervy - so prefer safety in numbers, especially if in with cichlids IME. Having kept 6 or 7 of them (now in Sams tank lol) in with my oscar and vieja, I think they may have even preferred a larger group than that - as they were easily scared.
I understand your two may have seemed perfectly happy, but if you didn't have yours in a group you could never say you
knew they were at their happiest/feeling safest (I'm sure there's a better word for that lol) adn that years of fish keeping research was wrong just because your two were ok.
I dont understand the latest trend on the boards to disagree with years of experience and research - if 99% of the experts say that they are shoaling fish and need to be in large groups, then why argue about it just based on your opinion? Why not say "Yes ok they do prefer it, but mine were ok in a group of two so it's not the end of the world" rather than "You're wrong, you're always wrong, you've got it in for me and who the hell are these experts anyway!". If you're so sure, why so defensive? Why not just agree to disagree, instead of making 99% of the fish keeping world out to be wrong to suit your needs?
It's just advice, you dont have to take it. It's not someone picking on you specifically just because they're handing out the correct advice to someone else.