Is the 18-200 THAT bad?

Being it's a kit for your wife, and you're getting the T4i, may want to consider getting the 18-135 STM (i.e., not the 18-135 IS). The T4i with the 18-135 STM wil allow AF when shooting video, it's smaller/lighter than the 18-200, and uses smaller (less expensive) 67mm filters.
The only reason I have the 18-200 IS is because of the price of D60 & 18-200 IS Kit from Costco.  As with the other 18-200mm type lens you can get good results when stopped down to f/8 - f/11.  When I want to travel light with a one-lens solution I use the 18-200 IS on the T2i.  If you're aware of the lens' weakness and strengths should be able to get good results.
Unless you intend on making prints larger than 8" x 10", pics should be just fine when viewing at normal distance.  So good tips/info not getting to hung-up on lens sharpness tests see the article: Lens Sharpness
You can find plenty of tests on the 18-200 IS with sample images to view/download just by doing a Google search for "Canon 18-200 IS Review".

Below is with the 18-200 IS @ 200mm

FYI can do some comparisons between the 18-200 IS and other lenses here: ISO Crops