[sulam]

I don't think it has much to do with virtualization, if I'm understanding correctly. You can think of it as the inverse of what your replay tool does. If you think of a service that does transformations on data:

Req --> Service --> Rep

Your replay service is a synthetic Req. I think the parent is proposing synthetic Rep. This can be useful in many scenarios where you effectively want to mock a downstream service.

[johns]

The industry buzzword for this is 'service virtualization' as mentioned above.