When cloning a large repository (~2G, general_delta format), using --rev to only clone a specific branch can lead to vastly increased clone times as shown in the table below:

--rev default	--uncompressed	elapsed time
		16:12,05
		15:21,41
		1:24,41
		8:18,24

The times have been measured on a Linux host using the following command:

time hg clone <options> <URL>

As can be seen, adding --rev default increases the clone time dramatically, while adding --uncompressed yields the fastest result. On Windows, the situation is even worse (~3 - 4 times slower).

It would therefor be nice if one could enable or disable clone options on a per-job basis, or even have something similar to Git plugin's "Additional Behaviours" which allows to specify "Advanced clone behaviours" (and many more).