That's the normal situation in England. Back to the mid 1500s, it's frequently workable, but the documentation runs out before that. There were two legal events that made English genealogy possible, the Statute of Wills in 1540 and Henry VIII's parish registration injunction of 1538. Before that, only the land holding gentry are traceable, and even then it's pretty hit and miss. In general, if a pre-1540 genealogy exists, it's probably in a herald's visitation and it's easy to find. If I can't google a source for it, I get pretty suspicious.