User blog comment:Legionwrex/Why Destroy is the worst ending (besides refusal)./@comment-1388547-20120707004302/@comment-4950455-20120708012250

So, really, if your Shep is Renegade, Control might not be for you.

I think that's thinking about it the wrong way. Certainly it might not be so good for everyone else in the galaxy, but if you've played your Shepard as a power-hungry ruthless sociopath up until this point, why would you stop doing so at the exact moment s/he could take control?