An implicit representation of sets

The 2003 paper by Gianni Franceschini and Roberto Grossi titled "Optimal Worst-Case Operations for Implicit Cache-Oblivious Search Trees" suggests a data structure that supports Insert, Find and Delete operations in O(log n) worst-case time while also being implicit and cache-oblivious. We explain the general idea of the original data structure, identify flaws and gaps in its description, and describe a reimagined version of one of the two major components of the data structure.