How often are you shooting a scene with more luminance range then Canon can handle...but not more then Exmor can handle...with close up foliage...and with wind so heavy that HDR or blending is impossible? Seriously, how many shots per year are we talking here?
A 3ev difference is in my experience often just the range you need to prevent clipped sky while retaining good shadow resolution. And the nature moves a lot, esp. if you look at 100% crop. If you doubt it, get out more :-> ... then you'll see it doesn't take heavy storms to make leaves and grass move noticeably. Are you watching closely ("The Prestige")?
There isn't a 3EV difference in practice, whatever DxO says. Remember that photographically 11 to 12 EV is a lot anyway, and, as I've said many times before, to hit this amount of EV range you have to begin including the light source itself in your exposure. There is then a slim window to make use of the 'extra' 1 stop or whatever, but the light source is normally much more than a 13, 14 or 15 EV range can cope with.
Remember there are many people on CR who have used and/or owned a camera body that uses Exmor. I don't see any of them changing.
The examples of pushing four or five stops is just academic. In all my 'landscape' type shots I'm only ever pulling about 1.5 stop, pushing 1.5 - max.