Board Thread:General Discussion/@comment-3392084-20130707145759/@comment-4913740-20130708012534

If Solid Snake is returning, he would not be voiced by the same VA as Big Boss. That would become hella confusing to hear them talk at the same time.

Solid Snake would need to be voiced by David Hayter in that case, but I don't think he can pull off the rookie Solid Snake voice anymore.