That's neat but how does one hedge a $800k loan with a max position of $25k? Idea seems spurious. The difference is substantially higher. Compare a pre-hike 2.8% with a present 6.8%. Your $25k hedge is going to be pointless.
Also even if you can't hedge the exposure in its totality, it is still worth hedging a fraction of it. "Under-hedging" is a common term in commodities markets - people often want to cover a portion of their exposure and leave the rest in the hands of mother nature.