Mitigate against accidental web service requests for massive amounts of data

[JimBacon]

It is easy to make requests to the warehouse for, e.g. the entire UK Master List, resulting in a massive response which, in many cases, is going to be unintended and probably badly handled.

Adding some measure to mitigate against this could
a. avoid burdening the warehouse
b. give the end user assistance in recognising their error.

One possible solution might be to limit responses by default with an explicit option needed to override the default.