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The OPE treatment that has been so successful in describing inclusive $\bar B\to l \bar \nu X_c$ decays yields sum rules (in particular the Uraltsev sumrule and its higher moments) implying the dominance of the $P$ wave $j_q = 3/2$charm states in $X_c$ over their $j_q=1/2$ counterparts. This prediction issupported by other general arguments as well as quark model calculations, whichillustrate the OPE results, and by preliminary lattice findings. Its failurewould indicate a significant limitation in our theoretical understanding of$\bar B \to l \bar \nu X_c$. Some experimental issues have been clarified sincea preliminary version of this note had appeared, yet the verdict on thecomposition of the final states {\em beyond} $D$, $D^*$ and the two narrow $j_q= 3/2$ resonances remains unsettled. Establishing which hadronic configurations-- $D/D^* + \pi, D/D^* + 2 \pi, ...$ -- contribute, what their quantum numbersare and their mass distributions will require considerable experimental effort.We explain the theoretical issues involved and why a better understanding ofthem will be of significant value. Having significant contributions from a masscontinuum distribution below 2.5 GeV raises serious theoretical questions forwhich we have no good answer. Two lists are given, one with measurements thatneed to be done and one with items of theoretical homework. Some of the lattercan be done by employing existing theoretical tools, whereas others need newideas.

Memorino on the `1/2 vs. 3/2 Puzzle' in $\bar B \to l \bar \nu X_c$ -- a Year Later and a Bit Wiser