Yea but in reality, 1 + 1 = 2, so the client should be using their own brain and not kidding themselves and doing the sums and asking, can I afford this? Have I got things covered if rates go up (every likelihood) etc etc, in other words, they have a plan B, C etc.
The old story IMO, think of things that could happen and ask, if they do, have I got it covered.