I have no problem with letting the man be subject to inquiry.
I just found it unusual that Issa would lambast Cunningham in writing a subpoena. Issa also fed information to Cunningham in his writeup that effectively alerts him to what is up.
It’s analogous to a judge writing a subpoena to someone that says “listen scumbag, you are associated with bad news and I got people in such and such department that say you up to no good so report to my committee on such and such date/time or else.”
All that Issa needed to write was “Report to my committee building number, room number at such and such date/time or else.”