Adding a Starter to Fermenter

Newbie question here, but I'm researching making my first starter and it arose. Using Mr. Malty's guide I am going to need around 2.18 liters of starter from liquid yeast for my 1.052 gravity ale. Is this pitched right in to the fermenter on top of the 5.5 gallons (around) of wort I will generate? I'm using a standard bucket style fermenter with a blow off tube, but this seems like it would leave very little head space.

 

For a starter 2L or over, I would let it ferment for 18-24 hours, then cold crash it in the fridge overnight or at least 4-6 hours. Putting it in the fridge will help settle out the yeast. Come pitching time, decant off most of the starter beer while disturbing as little of the yeast cake as possible. Leave about 500mL and then give it a good swirl and pour it into the fermenter. Less than 2L and I'll pitch the whole thing, mostly because I'm lazy and don't feel like waiting to chill it down. But over 2L, I'd be afraid the sour starter beer could throw some funky flavors into your beer.