I don’t remember proposition 1 explicitly stating that Ke = Kd…in fact Proposition 2 handles that relationship and states that cost of equity rises with the amount of debt used so that WACC stays constant.
Where did you find that? I was under the impression that Ke still rises linearly with increased debt in a world without taxes. Vu = Vl because taking on debt only “cuts the value pie differently”; debt doesn’t add any value to the firm in a world without corporate taxes. People can reverse or add leverage as they like, which is another reason debt doesn’t add value to the firm in the no taxes situation.
Under the first proposition, the costs of debt and equity are the same.
If the cost of debt was cheaper (which would make no sense with no seniority), then the value of a fully levered firm would be larger than the unlevered firm, naturally. So it assumes they are equal.
This is tackled in the second proposition, the cost of levered equity is higher than unlevered equity in a linear manner, leaving both the WACCs and the firm value unchanged.
In MMI, you’re not promising anything. Cash flows are divided proportionately. Therefore the cost of debt would always equal the cost of equity in this scenario.
Actually, you’re reiterating what I’ve said when you say
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I never said that Ke=Kd in the second proposition, because debtholders have a senior claim on cash flows. It tells you in a linear manner how Ke changes with more leverage, leaving the firm value unchanged from a constant WACC.
I don’t understand where we disagree. Maybe I’m misunderstanding your argument.