If I heard correctly かけずほど当てにならない, then was it 書けずほど?


I heard the following phrase in response to someone claiming that he had
researched documents about some historical figure. The person who had opposing
idea commented with:

> かけずほど当てにならない

From the context I guess it must have meant something along "I won't argue
with written things" (more literally "If it's not written down, it can't
true"), but the use of かけずほど is a mystery for me.

Could it be **書けず** ほど? What would be a grammatical rule behind it? Or could I
have misheard it?




As pointed out by l'électeur in the comments, the person probably said:

> 家系図{かけいず}ほど当てにならないものはない  
>  _There is nothing more unreliable than a family tree_




As pointed out by l'électeur in the comments, the person probably said:

> 家系図{かけいず}ほど当てにならないものはない  
>  _There is nothing more unreliable than a family tree_

