The reason for the GAH is that a novel is hardly ever genuinely cross-over and your claim that it is is rather like the claim in my recent post about age ranges. It induces much eye-rolling from the agent you've submitted to.
Nicola Morgan, the Crabbit Old Bat, is a multi-award-winning author of over 100 books across many genres. In this blog, she gives crabbitly honest advice to determined writers, and in her books, WRITE TO BE PUBLISHED, WRITE A GREAT SYNOPSIS, DEAR AGENT and TWEET RIGHT.