Seatpost polishing: technical questions

Even though I've now got my grubby hands on a 7075 30.4mm Syncros post, I'm not satisfied. It's black and I wanted silver. So failing finding a silver one to swap, I've been giving some thought to polishing. I'm not a lightweight, I ride with a long post, and this is a bike for riding, so the structural integrity of the post is important to me.

I'm tempted to try the caustic soda treatment to make my black post shiny, but I've got some qualms about alkali etching reducing the fatigue life of the post. Does anyone have the metalurgical knowledge to explain to this layman whether or not he should be concerned?

How much diameter is typically removed by a caustic/polish treatment?

Another option would be to source a 30.6mm post (they're also rare, but they do show up and tend not to be in such demand) and polish it down mechanically. I've got a 27.2 and a 27.0 Syncros post here and they both have the same inner diameter, so I guess the same may be true of a 30.4 and 30.6. Anyone confirm? How about a 30.9? Anyone suggest a technique to remove the necessary material uniformly without a lathe?

Thanks.

I managed to get the black finish from a post with a brillo pad or two.
Then went over with fine wet and dry followed by a good autosol polish up

Good as gold with minimal material loss

Proper anodize has a sealer on it, so caustic will eat into some areas faster than others.

I would go with Hunto's direction. I have Scotchbrite hand pads that break the anodize and follow up with Autosol. Comes out really brilliant.

Thanks guys. Now to see if I can pluck up the courage to take a Brillo pad to a brand new Syncros post...