I really don't know what they are on about. The front end just isn't harsh. The whole bike feels completely coherent to me. The back end has it's magic trick of taking the sharp edges of potholes, and the front doesn't. However,my arms are much more able to cope than my arse, so I don't feel like the front is acting in a way that's inconsistent.
My mate has the SLR. In his view, the new bikes trickery is primarily through the new bars, not the front decoupler, but even more of it is via having 32mm tyres. I'd be amazed if anyone found the normal Domane harsh - if you did, the damped bars and 32s would be cheaper than a SL (non adjustable back, decoupler front) or SLR (adjustable read and decoupler front). In the US, taking the S6 (the non adjustable back end, no front decoupler) as a base, the SL is another $800, and then the SLR is $1500 more than the SL ($2300 up from the S). Weight is pretty much the same.
The SLR 6 disc that my mate has is lush, but despite how similar they look, his is nearly double the price of mine.