Oh yes, you would only use this for a test with fairly simple problems. On the other hand, as I see it, it encourages the students to be more careful, and less likely to apply a slapdash "try it and see" approach.
And I've just received an email advising me that "Gateway Quizzes" allow precisely this sort of approach - as well as a host of other parameters.
WeBWorK Main Forum
Unlimited attempts at a complete homework set?
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