makes sense but I still would prefer to solve that problem with "batch" semantics at a higher level rather than depend on the wire protocol to bend over backwards
The problem with batch semantics is you do have to know everything up front. You cant just do one request and then 20 ms later another.
For DNS this might come up in format parsing. E.g. in html, First you see <script> tag, fire off the DNS request for that, and go back to parsing. Before you get the DNS result you see an <img> tag for a different domain and want to fire off the DNS result for that. With a batch method you would have to wait until you have all the domain names before sending off the request (this might get more important if you are recieving the file you are patsing over the network and you dont know if the next packet containing the next part of the file is 1ms away or 2000ms).
