This may be stating the obvious, but it seems that the purpose of this legislation will be to curb the following behaviour.
You have an income producting corporation.  You have some investments outside the corportation that you are whining about being taxed heavily on.  You lend your corporation money (which has to be paid back with interest of, I believe + or - 1% of the going rate.)  The corporation pays you interest, which you would be charged tax on, but it's probably minimal (especially given current interest rates.) The corporation invests the loan, say with highly speculative but lucrative returns, and pays lower taxes on the income or capital gains than you would. 
Eventually you will have to take the money out of the corporation (or your heirs will, after you die) and you will be taxed. but in the meantime, you've saved an enormous amount on current taxes.