@umich Thanks so much for this incredibly new way of looking at the lease or delegation rates. I assume you are looking at the NET interest rates for the investor, after factoring in the 10% commission and extra 7 days an investor must wait to have his delegation returned?

If I am right, the cost to the delagatee must be more than 37%.

For example, if a delegator delegates 1000 steem at a net rate of 37% APR for 4 weeks, he is tying up his steempower for 5 weeks (due to the one week cool-down period. This means he has to receive 1000 X 37% X % / 52 = 35.58 steem after the 10% commission. Before the 10% commission, the amount to be paid by the delagatee is 35.58 *10/9 = 39.53. For the 4 weeks, this is equivalent to an annual rate of 51.39%.

Is it worth it?

That depends on the value of an upvote and the value of SBD. Let's take the above example. If you have 1000 steem each 100% vote is worth $0.27. With the current price of SBD at $5.30, that makes a vote worth $0.64 for the author and $0.211 for the curator. In total that's $0.851 per 100% vote. Assuming that you are a shill voter and effectively only voting for yourself you could keep all of that and vote 100% 10 times a day or every 2.4 hours.

So now you have borrowed the voting power of 1000 steem and you can vote yourself with $0.851 10 times a day for 28 days. That gives a total return of $0.851 X 10 X 28 = $238.28. Remember, you paid only 39.53 steem to receive the delegation. At the present steem price of $4.33 it means it cost you $171.16 to earn $238.28. That's a 39.2% profit in just 28 days! The annual equivalent profit is 39.2%*12 = 470% profit per annum.

Conclusion

The delegator makes around 37% but the delegated makes 470%. The conclusion is that it is well worth leasing steempower, providing you can put the votes to good use.