when defining a report with the help of the excel plugin, and using 2 dimensions I get differences compared the web interface (adobe analytics web) with the same report definition. When just using one dimension the results are comparable.
Steps to reproduce:
1) Create report in excel plugin, make sure you have 2 dimensions (one on the first page of the wizard and another one as a dimension in the second page. 2) Make the same report in the workspace of the web interface. 3) compare those 2 reports .
You can also remove the 2nd dimension form the excel report and compare it to the excel report with the 2 dimensions and you will have a considerable difference totaling on the first dimension.