No breed is guaranteed to be gentle or safe, don't believe what the books say, that's like saying a person of a certain family line will never harm you; depends on the person, not the last name. Some families are more trustworthy than others, granted, and some are downright dangerous in general, but good and bad offshoots or strains come from all sorts of families and each individual must be judged on its own merit. Same with chooks. It's the most recent ancestors that are the best indicator of whether or not they'll attack people or kill chicks or display whatever bad behaviour. The breeder, not the breed, is to blame, since one person can in a few short generations take a nice breed and turn it to violent crap.
I've had great silkie roos, and been attacked by others. Even with blunt wobbly spurs they can cane you. (Not my rooster that attacked, or I'd have ripped his head off on the spot and been eating his corpse an hour later).
Regarding roosters: I have small children (not mine either) that roam the yard and paddocks at will so I cannot have violent roosters. So far, I've bred and kept hundreds of roosters of all sorts from all sorts of breeders, and in my experience the violence of a male breeds quite true; don't breed violent males or buy their offspring, and you don't hatch violent males. I keep all kinds of mongrels and purebreds, and in my experience it is not the breed, it is the most recent breeder that is the best indicator of whether or not you will get a violent rooster. If you get one, cull, do not breed, and that takes care of that, he can't pass on his aberrant mentality.
My silkies and derivatives have been among the smartest birds I've ever owned. They are a worthwhile bird, as long as you don't keep vicious ones. People say they're not worth it as meat birds but mine have always been among the best meat birds we have consumed, very tasty and tender and juicy meat on small but easy-fleshing birds. It may take more to fill a pressure cooker or spit, but I believe each silkie on average packs more nutrition than a common meat bird of larger size, which are commonly known to have nutrience uptake or synthesization insufficiencies no matter what they're fed. Males don't tend to need any help to put on great flesh, neither do the females not that I eat them often... But I haven't tried eating show-bred silkies and they'd probably be useless.
Silkies can be great, but if they're not, remember it's the breeder not the breed, never tar a whole breed with one brush because that's so overgeneralized it cannot be correct. Strain and breeder matter more than breed.