If you decide to cut it out, Robbied's link gives you an idea of what you're up against. Here's another, the top of an SR Laprade, the bottom of which I had to cut into quarters
, many years ago, before I could free it. I wish you better luck, skill, or both..
If it's an alloy post, and you have any sensitivity, you will both hear and feel when the hacksaw teeth have reached the inside of seat-tube- but despite that, I still have a small hacksaw-blade sized scar on the very top-inside of my seat-lug from this operation. It's good to have a few mementos to remind you of the benefits of grease, just as it's good to have rationalisations to make you feel better about your mistakes..
Roadking- A minor terminology nitpick.. I don't want to raise your dudgeon with this, but IMO, a seatpost should ideally be slacker than a true interference-fit. To me, an interference-fit is a fit that is designed not to move, and needs a hammer or press to dismantle. It may be interference-fit seatposts (and lack of grease) that cause such siezures in the first place?