How can we teach students to use code structures that support readability? How common is it for students to choose less readable (but still functional) alternatives? We explore these questions for a specific novice structure choice: using sequential if statements when conditions are exclusive (rather than using else-if or else). We created and validated an automated detector to identify this anti-pattern in student code. Running the detector on 1,764 homework submissions (from 267 students in an intermediate CS class on data structures and algorithms)showed that this pattern was common and varied by assignment, with 3% to 50% of submissions using this pattern across 12 assignments. However, the use of the sequential if anti-pattern did not preclude the use of else-if: up to 34% of submissions used both forms across assignments. Further, students used sequential if statements in surprising ways, such as checking a condition and then the negation of that condition, indicating a more novice level of understanding than expected for an intermediate course. Hand inspection of the detector-flagged cases suggests that sequential ifs for exclusive cases may be a code smell that can indicate larger problems with logic and abstraction.