Conyers asks Bush to waive executive privilege and to allow Bush's pardon lawyers and other experts to testify.
Now why on earth would the president make it easy for the witch hunters to continue with their endless investigations that have gotten them nowhere?
So, I suggest Bush answer Conyers, this way:
Mr. Conyers, INVESTIGATE THIS.
[Update] The Hill shows us that basically this IS what the Wite House is saying to Conyers.