  We show that it is necessary to go beyond a single hadron (beyond the
quark-antiquark or three-quark systems) in order to distinguish the colour
structure of the effective quark-quark interaction and the relevance of 3-body
forces. We critically discuss the proposed models which suggest the dimeson
bb\bar{u}\bar{d} to be bound by ~ 100 MeV and the cc\bar{u}\bar{d} dimeson to
be unbound. Only experiment can judge. We estimate the probability of producing
bb-\bar{u}\bar{d} at LHC by double gluon-gluon fusion and search for a
characteristic decay.
