This section does not apply to bonds issued under an enabling act that specifically states that this section does not apply. Whenever a State unit simultaneously issues bonds authorized under 2 or more enabling acts, the State unit may allow submission of a bid that: is for bonds authorized under 1 enabling act; and is conditioned on the acceptance of 1 or more companion bids for bonds authorized under 1 or more of the other enabling acts. Whenever, as a whole, a set of bids under subsection (b) of this section yields to the State unit more than individual bids, the State unit shall accept the set even if 1 or more of the bids in the set yields less than the individual bids.