of course it's never "the aim", they want the film to test well and be awesome. but you're deluded if you don't think it's almost the norm, not the exception, that films are re-edited/reshot from minor to major degrees following the reactions to those screenings.
Well first of all you were talking about reshoots, not editing. I'll throw out some guesstimate numbers from my knowledge but it probably costs a studio about $10-15k per week to run an editorial team. To run a production on location for example, with your talent/stars you're easily looking at $100k+ per day minimum. For a movie in full swing that can probably hit $1m/day. Where do you think a $200m budget goes? So there's
quite a difference between re-shoots and "re-editing".
Editors can usually cut up until about 6-8 weeks before release depending on a lot of things. So yes, they're "re-editing" after a lot of test screenings. That is normal. But re-shooting after test screenings just isn't, sorry. It happens, obviously. But it's never the norm. Especially if we're talking about test screenings that only happen 1-2 months before release.
You can call me deluded, but the fact I work in the post production department for one of the 6 major studios probably says otherwise
NB: Most studio titles have "additional photography" budgeted from the start, and time locked down with their talent. This is not the same as "re shoots"...