Presumptive, Part 2

A few posts ago (April 8), I opined as to how the use of "presumptive" in campaign stories (as in presumptive Democratic nominee John Kerry), while technically correct, might not be a good idea because a number of our readers likely would misinterpret it as presumptuous.
Using presumptive has become the fashionable thing this election season. I stopped counting at 100 times I heard or read it in one recent week. Well, the question arises, how likely -- really -- is it that the word would be misinterpreted? So I conducted a little experiment. I built this sentence into the usage part of one of my weekly copy-editing class quizzes:

Smith said it was presumptive/presumptuous to think he'd do that.

More than a third of the students in this 50-student class chose the incorrect presumptive. That a third of the students, juniors and seniors who are journalism majors, misinterpreted that when the words and explanations are in their textbook, says one of two things. First, you can fashion your own comment about journalists and journalism education. But seriously, it indicates that confusion is just as likely among our readers for whom the daily paper does not come with a dictionary.

Now, I don't mind occasionally sending readers to the dictionary when the word is the exact right word and there's no really good substitute or misinterpretation. An occasional ersatz or eponymous does the soul good. But when there are really good substitutes for presumptive (likely, expected) that don't lead to misinterpretation, we should use them.