There you go again, saying you know what BP knows and what BP thinks. The truth is, you have NO CLUE, nor do any of us. There are many possible reasons as to why BP has not named the backup, unfortuneatly you are blind to them. Let me give you a crash course on how the things work:
1: He is, in fact, trying to save face as long as possible. He knows Henson was brought here to be the future, and now that it's obvious he realizes that he isnt (shown by the fact that he did not play at all last year after we knew the year was a lost cause and could have played him without consequence, and by the fact that he has given Romo more reps in both TC and games) he and JJ dont want to have to admit they *** up royally by putting him 3rd on the DC, behind an undrafted FA. In time he will be forced to name Romo the 2nd QB because Henson is just too unreliable for even JJ to stand.
2: He doesnt want to hear about it for the next 2 weeks. No matter who he names, people will bash him and the papers will whine and everyone with a microphone will ask him how he could be so stupid and so on and so forth, especially if he names Romo the starter.