I understand your logic - but as I indicated above, I think in almost all cases, the employer (through it's employees) is *still* going to be a fiduciary - maybe not THE Plan Administrator, but still a fiduciary, and as such, may still have liability. Plus all of the individuals actors who perform fiduciary functions (whether they know it or not) can claim the title as well...
I disagree with the risk transference concept. The concept of co-fiduciary liability comes into play as well, and even if their is a "proper" delegation to a 3(16), many other factors come into play with respect to other fiduciaries, etc. I have yet to see a case where there was such a clear cut case of proper delegation (without interference) such that another fiduciary would be dismissed from a lawsuit. It may be that we haven't seen any "3(16) cases yet - but in my experience ... well let's just say, I wouldn't want to defend the plan sponsor in that situation.