I think it's important to be clear about the limits of federal spending power. Federal spending power doesn't translate into a regulatory constitutional authority for the federal government. While the federal government may, in any particular area, provide grants or contributions, that spending power--in other words, the creation of contractual relationships--does not translate necessarily into the federal government having the authority to go in and regulate conduct that would otherwise be in the jurisdiction of the provinces. So the mere fact of giving money would be insufficient, unless we were talking about giving money in an industry that was already under a federal constitutional head of power.
On June 13th, 2006. See this statement in context.