Looks like an apples to oranges comparison. Notes behave like an underlying, not an option. I find it hard to force fit any of the greeks to them, with the possible exception of rho.
As an underlying, notes do have an option embedded within them; the pre-payment option. Dr. Friedman's NTANSTAAFL implies that the interest rates we receive are higher than they would otherwise be were it not for our implicit sale of this option when we buy a note. That option's value does decay with time (to the lender's benefit). Since the lender is short this option you could actually claim a negative theta on that.