Before I ruin this thread, on a serious note...
OP: Normally when you decide to go into manual mode, you want to downshift, right? So all's good when you grab the knob and make the switch... From then on, why wouldn't you just use the paddles (for both upshifts and downshifts)? The whole point of those is that you don't have to take your hands off the wheel to shift like us MT peasants do. I'd think grabbing the knob again would indicate you wanted to go back into automatic mode.
I'm not saying your situation is normal (someone with an AT can confirm that), it just seems weird to me that you'd choose to upshift like it was a Volvo S40 when you've got flappy paddles like in a Ferrari 458.