There no point changing up at max torque, torque itself has nothing to do with acceleration, power does (i.e. how many times the torque figure can be transmitted a second).
If you are in a hurry, max power occurs way after max torque.
If you are a real hurry - (on track, or misjudged overtake or something) then you will always accelerate quicker right up to the red-line than changing up earlier.
The reason for stretching the gear out is that even though the power tails away slightly, you are still making maximum use of the lower gear ratio which more than compensates, and to a lesser extent dropping the engine more into its powerband when you do change up.
The second you change gear you are losing approx 20% acceleration due to gearing differences (figures from my own cars telemetry).
This is indisputably true for petrols, although I would be slightly less sure about some diesels that are asthmatic (am not saying Alfas are asthmatic btw
SandyS on here also carried out some telemetry for his GT 1.9 and always found it better to get the most out of the gears than change up early, for his car at least.
T-sparks dont give issues because people rev them, itheyhave issues because folks dont change their cambelt every 3 years or 36K miles.
"TB's tips for long engine life"