If you compare the published Columbus weight specs against actual, the actual is almost always heavier. Not to the extent of those Reynolds tubes though. Maybe Reynold's tooling is getting old and they are not trying very hard to tune everything during the drawing process? Seems plausible to me anyway.

As an aside, I bought some Reynolds seat stays about 5 years back or so and another set recently and the new ones were about an oz heavier each piece. I was surprised...and not in the good way.

Another aside, I lived in the Cleveland area for a while where Joe Bringheli resides, and he let me weigh some of his Dedacciai tubing stock as I looked for some light pieces. There is this nifty down tube they make where it's 31.75 at the head tube end and 35mm at the bottom bracket, and there was more than 30 grams difference between samples.