The Batman by-election actually saw Shorten get the bounce with a swing to Labor.
Tracking polls also reflected that the 65s and over in the electorate were not deterred by the franking announcement. Given all the polls were saying the Greens were well in front right up to the franking credit announcement it may be reasonable to say that at worst it did no harm and at best it actually helped Labor because the Greens slammed Shortens proposal but the momentum swung back to Labor.
The ones jumping up and down about franking credits are in the main already coalition voters so no loss to Labor!
