Attention is called to the process propagation velocity preferred position in the collection of parameters of focal models and the quantitative assessment significance of a reduced value <$E zeta~=~v "/" c> even for models with constant velocity v = const (c is the elastic wave velocity). The scheme of determination of the ratio <$E zeta> by records of three stations logically completes the author's computational algorithm based on the time integration of a displacement with weight factors <$E f(t)~=~t sup n>, n = 0, 1, 2,..