Thanks for the mention! It exists and it works. We've learned that the demand for yield in this manner far outpaces the people ready to start doing lightning payments, which means that capital can be extremely well allocated, but still be low yielding. Deploying to lightning is not free, so positive returns are not guaranteed. That said, we've deployed 66 BTC to date and are returning between 0.6% to 1.5% APY on self custody bitcoin.