Laird, if Venus were 'out of its orbit' as recently as Copernicus' time, we'd still see the effects of it.
Let's face it, astronomers of those times (both Ptolemy's and Copernicus') just didn't have the instruments to make accurate calculations as we do today. And there's also the very human element of just plain error. I don't see this as an issue at all.
The process we're suggesting that Ptolemy and Copernicus were not able to competently complete involved counting how many days in a row one of the brightest bodies in the night sky was visible, then not visible. You're right - it must be the lack of modern instruments.
Also, we do still see effects, most notably the continued gradual slowing of the rotation of Venus.