On Tue, 6 Dec 2011, Anne van Kesteren wrote:
Especially changing the way <head> is parsed is hairy. Every new element we introduce there will cause a <body> to be implied before it in down-level clients. That's very problematic.
Yes, I consider adding new elements to <head> to be very very bad for this reason. Breaking DOM consistency between supporting and non-supporting browsers can cause adding an intent to cause unrelated breakage (e.g. by changing document.body.firstChild).
