@knownissues
-When using @code{\mergeDifferentlyHeadedOn} with an upstem eighth
-or a shorter note, and a downstem half note, the eighth note stem
-gets a slightly wrong offset because of the different width of the
-half note head symbol.
-
@ignore
@c TODO investigate! Sometimes it works, sometimes not. --FV
The requirements for successfully merging different note heads that