Were the guards immediately hostile? Or did you see the screen shake before they went hostile?
I didn't notice screen shake, but I was in 3rd person (my usual) and looking around so I could have missed that. No, they definitely weren't immediately hostile. I was able to follow the perimeter sentry on the return leg of his patrol route (it was easy to walk behind outside of detection cone), and with a bit of work avoid runnning and stay out of of his vision when he turned back to head out. It was the approach to the city gate that was problematic as there are two guards (perhaps more?) with their backs to the city wall and no way to get more than 90 degrees off center. It seemed that they detected me as I drew even with the stables, I believe one of them hustled down the stairs, but the sun was setting behind the city wall so what I actually saw was a guard charging across the killzone from the direction of (base of) the stairs to confront me over my bounty (whats 2000 septim between friends, friendo? ).