I double pitch dry yeast for big beers. Dry yeast is very cheap. And it requires little to no effort to suspend it in sterile water before pitching as opposed to using a starter.
My understanding of dry yeast (based on reading several books, including Briggs, as well as reading various websites (none of which are commerial-owned)) is that they are sold ready to pitch immediately after hydrating. As others have said, this is based on how they are produced, purposefully arresting them at a stage of development so that they are primed for being placed directly in wort. This is proported to give the yeast the advantage of having the entire population primed for multiplying to the correct number of cells for the amount and concentration of wort in which they are pitched.
Having said this, you could definitely do a starter with dry yeast. But you lose the advantage they tried to create for you. And to me, I'd rather spend $4 or $5 for an extra packet of dry yeast than do a starter. But I'm sure you'd get great beer either way.
My understanding of dry yeast (based on reading several books, including Briggs, as well as reading various websites (none of which are commerial-owned)) is that they are sold ready to pitch immediately after hydrating. As others have said, this is based on how they are produced, purposefully arresting them at a stage of development so that they are primed for being placed directly in wort. This is proported to give the yeast the advantage of having the entire population primed for multiplying to the correct number of cells for the amount and concentration of wort in which they are pitched.
Having said this, you could definitely do a starter with dry yeast. But you lose the advantage they tried to create for you. And to me, I'd rather spend $4 or $5 for an extra packet of dry yeast than do a starter. But I'm sure you'd get great beer either way.