I don't think Nintendo typically forces their studios to produce products they don't want, but they probably encourage them to make games that are already based on an established IP if they can. While there are obvious exceptions, new IPs tend to require superior quality and a much larger marketing budget to sell to nearly the same levels as an established IP; and even then they tend to fall short.
I'm reminded that Rare was working on a videogame late in the life of the N64 called Dinosaur Planet and Nintendo, after noticing that the main character was a fox, convinced Rare to use the Starfox IP which resulted in Starfox Adventures: Dinosaur Planet. Similarly, in interviews with Rare early in the development of Metroid Prime Rare claimed that they asked Nintendo to produce a Metroid game. Now if these cases were not just PR it would imply that there is more freedom than people are implying
Of course, to the typical "grunt" developer, it doesn't really matter whether the producer decided that they asked for a particular IP or if Nintendo forced it upon them; the decision was made by someone much higher than them without their input. While we don't know why the management at Retro made their decisions, it is plausable that working on a string of successes like Donkey Kong Country Returns and Mario Kart 7 may give them the opportunity to expand their team (having 2 internal development teams for example) or the freedom and resources to develop a big budget game for the Wii U.







