In BMW own press reelase of the M5 they describe how more gears and higher revolutiosn could be better than alot of torque in a desriptive way:
"Engine speed has a major influence on performance and torque: As far as maximum torque (520 Newton metres) is concerned, the ten-cylinder matches the eight-cylinder power unit. Nevertheless, the new M5 beats its predecessor in all disciplines relating to driving dynamics. This phenomenon is also connected to the engine speed. A case in point: if a cyclist changes down when going uphill, he must pedal faster but he will master almost every gradient no matter how steep. If he does not change gears or if he even changes up, he needs a lot more energy or he has to get off the bike.
If there are two cyclists with the same amount of stamina, it is always the cyclist who pedals faster that wins the race.
The logical consequence is that the new M5 with its high-revving engine also effortlessly outdoes all direct competitors who exclusively rely on the “torque concept” of an eight-cylinder engine with an increased cubic capacity. In addition, this engine’s superiority can be put down to the fact that the concept-related extremely high torque of competing engines has to be transferred via a massively reinforced and heavy drive train – added weight and mass that must also be accelerated. Thanks to the V10’s high-revving concept, a considerably lighter drive train can be used and closer gear ratios can be achieved.."
http://www.m5board.com/articles.php?id=34&page=3