I downvoted you because your post seemed unnecessarily pedantic and condescending to me. I think it was pretty clear that GP was casually (or accidentally) using "retina display" as a generic term for "high DPI display".
Still: targetting "retine display devices" is wrong for a multitude of reasons. You don't want your website to be tailored for a device which has 4x the number of pixels of another very specific device made by one vendor only. That is not the problem you are trying to solve.
The problem you are trying to solve is creating a DPI-independent site layout which exploits the resolution and estate available, while degrading gracefully on lower class devices.
If your solution to that problem is making your website hardcoded to fit two devices made by one vendor, as long as they remain true to leaving everything pixel perfect as they are now, for all eternity, needless to say, it's not a good nor elegant solution.
It's the "This website was made for MSIE" of olden days all over again, only this time for Apple-devices. And thats just not going to cut it.
