How does the recorder decide when to use .resources and when to use .exec, as I think I see events I would expect to be sequential in .resources blocks

Hi all,
I’ve imported a HAR file that was exported from a Chrome Dev tools session. I use this approach as our application also uses SSE which the recorder doesn’t support.
The Gatling/Scala file produced as a result of this includes a number of get/posts as part of a few separate .resource blocks.
Playing these Gatling scripts I’m seeing some errors possibly because the requests are arriving in an order unexpected by the server as the requests are part of the same .resource block, which allows parallel execution. I don’t see the same errors when performing the equivalent actions via Chrome.
My question is how is it decided when requests can be part of the same resource block?
I’m wondering if my application is broken and actually allows parallel requests but isn’t manifesting in normal usage, or if something is going on with conversion from the HAR to the Gatling file?