Does moving ad groups between campaigns affect performance?

[jrm_adwords]

I recently took over management of a website that has a significant AdWords investment associated with it. There were a number of campaigns that, for whatever reason, were pretty badly organized in terms of their advertising goals (general site traffic vs. specific product sales, for instance). So, I created a few new campaigns, moved the adgroups around to make more sense, and deactivated the old campaigns.

I was rewarded for my rationality with a significant drop in number of impressions across all the campaigns. After a bit of study and panicking, I re-enabled the old campaigns, such that some of my ad groups are now appearing in two active campaigns. My impressions have gone back up; whether I'm back to where I was before the change is unclear due to the uncertainties of holiday web traffic, but my reports are showing that the doubled ad groups are producing impressions in both the campaigns in which they appear. The "average position" ranking of the keywords in the different groups are sometimes quite different, with some tendency for the old campaigns to have higher ratings than the new campaigns. I'm tempted to attribute this to differences in quality scores, but I'm enough of a newbie with AdWords to question whether this is correct.

Anyway, does anyone have any insights or advice into this? Should I give up on my attempts at rationality and go back to the old campaigns? Are there problems with running the same ad groups in multiple campaigns? Am I shooting myself in the foot here?

Thanks much.

[artmacc]

A few questions for clarification... Did you duplicate the ad groups in the new campaign...same max cpc, same match types? Did you duplicate the adverts in the new adgroups vs old?
Google serves the ad with the highest quality score. The drop in impressions maybe seasonal especially if you are focused on btob. I saw a 22.9 percent drop in impressions against our weekly averages.

[PPC-Coach]

I'd stick with the old campaigns and just clear out the clutter from them. The account with a history is going to out perform the newer account with all other things being equal. Also, both are getting impressions, but they're being split between the accounts, so the new account will get lower ad positions then the old one for the same costs.