4204 Bond Question

[ERISA25]

Section 4204(a)(2) provides that if a buyer defaults on its withdrawal liability obligations, the Seller (or the bond if a bond is used) shall pay to the plan an amount equal to the withdrawal liability that would have been due but for Section 4204. This seems to suggest that no matter the amount of withdrawal liability owed by the buyer (i.e., even if that amount is less than the bond amount), the fund may collect the entire bond amount. This seems rather unfair in light of the fact that the buyer's withdrawal liability is based, in part, on the seller's contribution history. Has there been any guidance with respect to this point? PBGC Opinion Letter 83-10 touches on some of the fairness issues, but it is not directly on point.