Safari generally implements standards as they mature.
Chrome generally implements everything new and shiny, no matter how underspecified it is, and with blatant disregard to whether or not it breaks the web.
I don't disagree with regards to new standards, but that doesn't change the fact that existing, well established standards are often broken in Safari (see the bug I linked in the parent comment). These bugs are much more likely to break the web than Chrome's half baked bleeding edge features because there's already a huge body of web software that relies on them.