Restraining git pull/fetch to the current branch

While trying out git on a large repository (10000s of commits, 1000s of branches, ~2.5Gb when packed) at work I noticed that doing a pull was taking a long time (longer than I was prepared to wait anyway).

A quick test showed that a small repository (1 commit, 24k .git/objects) with 1000 branches took 1m30 to do "git pull" (local xfs partition). I don't know if this is reasonable or not, but all I actually cared about was updating the current branch, which "git pull origin <branch_name>" did in 0.3s.

So what I would like to know is: is there any way to make a pull/fetch with no options default to only fetching the current branch? (other than scripting "git pull/fetch origin $(git symbolic-ref HEAD)" that is)

TIA