I polished the barrel on my XD40 along with the frt of the guide rod. Then I polished the slide, barrel, and guide rod in a Taurus. No issues at all, it may have made the XD "smoother". Strictly a feeling. Have at it! The bluing will polish off.

Good to know Thank you very much. What did you use to do it? White Vinegar? Or something else?

I'm really new to polishing, but here's what I've learned so far (in a nutshell). I started with a Dremel and those tiny little polish tips. Like cutting your lawn with wire cutters. I bought 2 buffing wheels from the tool dept. at lowes. Firm and polish. Right near them were 4-5 different polishing compounds in stick form. I bought "hard metals" and one other. Check the labels and reason them out. Mounted the wheels on my grinder (3450 rpm) and went to work. You apply some material from the stick to the spinning wheel, then your barrel. Get some friction going to generate heat. I've read some pro polishing stuff on the web, they all start by preheating the part to 150 deg. It'll take 15 minutes to get a chrome like shine. There a learning curve for desired results, but it's a forgiving one, you really can't screw up.

Don't forget to put up pix. Here's a link to a couple I put up after doing the 709 matte stainless barrel & slide. Not done yet.
Just bought a Taurus 709 ss Slim for my wife

i just finished polishing my p-11 barrel. mine was not blue however. mine was the rough grey. i started with the feed ramp. it was so easy and productive, that i ended up doing the chamber, center lug and barrel hood. made a very big differenc. now the action is silky smooth.