I don't think Mercedes intend to handicap any of their customers in any way, as pointed out, it's bad for business. But I do believe they intend to field the best powerplant package for the Mercedes team. Even today each team design and incorporate many components in the engine package, such as the intake system, exhaust system, ECU programming, cooling system, and alternator, just to name a few. We all know that in the case of Renault engines during the blown diffuser days of 2011, Red Bull had their engine functioning in a manner quite distinct from the rest of the Renault engined teams.
The 2014 technical regulations are going to introduce a very complex package. There's the basic engine lump, itself a complex puzzle. Add to it a turbo with heat energy recovery system and motor/generator unit, a kinetic energy recovery system with a motor/generator unit, energy storage device(s), switching devices, alternator, and the programming in the ECU. Everything is a set of compromises, when do you harvest energy from the turbo, when do you use that energy to spool up the turbo to boost low end power, how much energy do you use and at what rate, when do you harvest kinetic energy from the drive train and at what rate, do you have the HERS shoulder most of the load in doing that, and at what rate, how will it affect rear tire wear, all these questions each team will have to decide on when they program the ECU.
It's like a game of chess, everyone starts with the same pieces, but how you play the pieces decides the outcome. Mercedes is good at playing this game, they have tremendous resources, money, and expertise in this game, unlike Force India (for example), who basically have to figure it out all by themselves, unlike the mega giant and powerful Mercedes corporation. At this very moment Mercedes are spending a lot of money, and have a lot of people, computers, and simulations working on this puzzle figuring out the optimal compromises, in order to have the most efficient, reliable, and effective system when the season begins in 2014.
Why do you think that Bernie and the FIA fully support the current tire situation and the Pirelli tires? Because domination by any one team is bad for business and these tire regulations make life hard for Red Bull, and give others the chance to win titles. It's no accident or surprise that in the first 7 races in 2012 Red Bull were not dominating, that only when everyone started to figure out the tires and things settled down enough so that the teams spending the most started to assert themselves did Red Bull and Vettel put on a march to eventually win the titles.
Why do you think that Bernie and Ferrari are making ugly noises about the 2014 engines and attempting to kill off the change to the 2014 engines? Because they are looking over at the Mercedes team with Hamilton and Rosberg and saying ..