  An estimate of the convergence radius of a simulated CDM halo is obtained
under the assumption that the peak phase-space density in the system is set by
discreteness effects that operate prior to relaxation. The predicted
convergence radii are approximately a factor 2 larger than those estimated for
numerical convergence studies.
  A toy model is used to study the formation of sheets of the cosmic web, from
which DM haloes form later. This model demonstrates the interplay between phase
mixing and violent relaxation that must also be characteristic of spherical
collapse. In the limit that sheets contain arbitrarily many particles, it seems
that power-law profiles are established in both distance and energy. When only
a finite number of particles is employed, relaxation is prematurely terminated
and the power laws are broken. In a given simulation, the sheets with the
highest peak phase-space densities are those that form from the longest waves.
Hence simulations with little small-scale power are expected to form the
cuspiest haloes.
