My first starter

[Optimus Prime]

My next batch is a high gravity wit. The calculator says my smack pack is not enough and I need to grow more yeast. It says 2L of starter is enough.

Question 1: as I watch videos, I see a lot of people making smaller starters, and each day increase the size of it until they have what they need. Is this necessary? Or can I simply start with 2L of water and the appropriate amount of DME and call it a day?

Question 2: if I am not trying to stick to matching a particular style, is there any reason not to start with the starter wort to finish filling to 5 gallons? Otherwise, I need to buy another bag of DME.

Thanks for your feedback.

[Oginme]

To answer your questions in order:

Question 1:  Generally, people will start with a smaller starter when they have only a very small amount of yeast to build from.  If you are working with 50 to 100 billion cells from a typical pitch of Wyeast or White Labs, you will have enough to go straight to a 2 liter starter. 

Question 2:  Pitching the full starter volume is a matter of personal preference.  Generally, I make my starters well in advance and cold crash them to decant most of the starter beer off the yeast cake.  I am also overbuilding my starters to save some of the yeast cells for teh next brew.  If you go for a vitality starter, you are making your starter just 12 hours give or take from the time you need to pitch it and then pitching the whole starter wort, beer and yeast into the carboy with the freshly made wort when the starter is at high krausen.