I agree with you in part @simonwelsh , but I also have thought about the counter argument, that this command is usually only run in a development environment. `composer install` is the correct way to install on production, where --dev should not be the default.

I agree it's annoying to users who don't want to run test cases, but I'd think that running phpunit should be standard practice these days, and the less we have to rely on pear and use a standard mechanism for install (composer) the better.