Two bonds are both 'senior unsecured' but one is issued at the operating subsidiary and one at the holding company. Which recovers more and why?

The operating-subsidiary bond almost always recovers more. Opco creditors have a direct claim on the entity that actually owns the assets and generates cash flow, so they're satisfied from opco value first. The holdco bond is structurally subordinated — it only reaches the residual equity value that remains in the subs after opco creditors are paid. Same label ('senior unsecured'), very different position in the real waterfall. This is a classic interview gotcha on structural seniority.