After our company upgraded the Sharepoint licenses and the infopath browser-enabled forms could function I worked for ages on my form. The question was, will this technique work with forms rendered in the browser.
The answer: problems were numerous.
The browser forms would give errors based on filtering the target of a rule, a step needed to set the submitted data fields, Field[@Name...]. But the error only occured sometimes. Testing for the cause was tough: I think, [1] once the error occurs, then it will always occur; [2] I believed it worked provided the form template was saved with no filtered targets. This can be seen by selecting the Rule Inspector. If there are targets with filters, it does not recognize them and shows rule as invalid. So if I remove the filters, save the form as [new title], close and reopen in desing, then the Rule inspector gives no errors. Then I would re-hack the manifest file (by the way I used a shorter way to filter the target here by using Field[1], Field[2], Field[3], etc., you don't need to put the [@Name="Title"] for the @Name="Title", if Title is the first field in the xml file, it can be referenced using Field[1], but this is still a manifest hack) Then immediately publish and the form rendered in the browser would submit the multiple lines to the SharePoint List.
Another issue was the 16 rule recursion threshold, but I couldn't spare the time to test if it would fail in a browser-form. I thought one test I tried showed that the method to bypass the rule does not work on a browser-form.
Bringing me to my last point: the Server maximum operations was the final straw. That was too much and I made one form browser-enabled to utilize some specific benefits (input parameter from a WebPart) but the form I was making that submits many lines to a SharePoint list was made so it could render in a browser with the input parameter (supplied in URL query) but the user was instructed to click a link that opens the form in the client application, and instructions provided to select the single entry from a dropdown that matches the input parameter that they saw on the browser page. No problems if it is a client-opened form: rules, repeating tables, all that stuff.
Great post Amieqq