  The problem of demixing in a binary fluid mixture of highly asymmetric
additive hard spheres is revisited. A comparison is presented between the
results derived previously using truncated virial expansions for three finite
size ratios with those that one obtains with the same approach in the extreme
case in which one of the components consists of point particles. Since this
latter system is known not to exhibit fluid-fluid segregation, the similarity
observed for the behavior of the critical constants arising in the truncated
series in all instances, while not being conclusive, may cast serious doubts as
to the actual existence of a demixing fluid-fluid transition in disparate-sized
binary additive hard-sphere mixtures.
