Please note that I am not a lawyer, or an accountant for that matter, though I do know a thing or two about the Income Tax Act.
I don't think that the plan, as you have set it out, is possible. Even if it were, the CRA would probably determine that your plan was abusive. Assuming that the structure was kosher with respect to the rest of the income tax act, there is still the general anti-avoidance rule (GAAR) to contend with. The whole thing stinks of an abusive tax plan, and assuming that you were audited, reassessed, and you objected and filed with the courts, I think that the Tax Court of Canada would let the CRA's assessments stand.
That said, I think it might be interesting to consider the possibilities here. Please note that this is all a speculative thought experiment. Suppose you do set up a mutual fund trust. At creation, the trust has no assets or only nominal assets. The mutual fund trust beneficial ownership (the fund units) are sold to your TFSA, and since the value of the units is nominal, you do not end up over-contributing to the TFSA to purchase the mutual fund trust units. Then to get assets into the mutual fund trust, you loan funds to the trust in exchange for a promissory note. You are also made the manager/trustee of the trust so that you can manage its trading activity. The trust pays you income in the form of interest payments (which would still generate a lot of tax), and distribute the excess earnings to your TFSA, where supposedly they would accrue tax free.
I don't really see how this could work. You don't deal at arm's length with the mutual fund trust since you are also the trustee/manager. I think a bigger problem is that the TFSA can only hold up to 10% of a given share class of a private company, and I think you need to deal with any private company in which your TFSA invests at arm's length. There is also the question as to whether an investment in such a mutual fund trust would be admissible to be held in the TFSA. Any investments in private companies in the TFSA need to always meet the admissibility criteria, unlike an RRSP, in which it only matters when the relevant securities are acquired (if they subsequently become ineligible, then I don't think anything happens). If a private investment in the TFSA is found to not meet the admissibility criteria, then any income generated will be taxed accordingly.
Well, at least it was fun to think about this.