Well of course one can get it in the proper position. However the typical way that many measure their contact points on the bike won't give the correct saddle position in relation to the BB. Many tend to only think of the distances between the saddle and the bars or hoods.

The caution I made was just to start them thinking about it. With my leg length the difference between 1 degree of seat tube angle is only about a half inch. But that might make a difference for some that are already have their saddles far back in the clamp or far forward. But then again 1 degree of seat tube angle will be unusual for just a change in size of the same model.