Looks like some good insurance. There have been way too many people on here, with secondary cam sprocket issues, cracking the sprocket with aftermarket cams. Even when installed by some of the best reputable shops.
Yes, we can do it but it is not needed, the MMR sprocket wont break or shear the key off, the double key is only needed for the balancer on supercharged applications, the crankshaft does not need to be keyed any further back than the balancer as this further weakens the crankshaft snout.