"Okay, I guess that you agree that your smooth talk won't get you anywhere with the Matron," Harry reasoned. "So what are you proposing…that you steal Snape's wand out of her locked office desk? Planning on knocking her out first, or erasing her memories afterwards?"
"Mr. Potter, I do not have to stand here and listen to your scurrilous attacks."
"No, you certainly don't…neither of us need to be here right now."
"I can't let you go until we know how strong your shields are right now!"
Harry shrugged. "So test them yourself…I don't know why you'd trust any description that Snape provided in the first place."
"Professor Snape!"
"Yes, Sir. Professor Snape."
Dumbledore drew his wand.
"Aren't you going to at least bark at me first to clear my mind?"
The Headmaster sucked in a deep breath.
"What I am going to do, Mr. Potter, is cancel my privacy protections. At that point in time, you and I will leave the Infirmary and travel up to my office. Once there, I will take up your suggestion and test the strength of your Occlumency Barriers myself!"
Harry stared at the Headmaster for a moment, then allowed his lips to curl up into a slight smile.
"Well alright, then," he declared. "Let's do it."
As the two wizards left the Infirmary, the-Boy-Who-Lived couldn't help but notice that the Headmaster's robes were now billowing behind him much like Severus Snape's always did. This special effect, when taken along with Dumbledore's thinly-disguised anger, proved inspirational.
Careful to stay two steps behind the Headmaster, Harry began humming the martial melody from the musical score to "The Empire Strikes Back."
"Da-da-dum, dum-de-dum dum-de-dum…."