Hi Ed,

> Also, how much of difference in tube diameters would you
> suggest? 5%? 1%?

I'd think that something pretty small like 1% may be enough. But you may run into some issues if that difference becomes less than around 0.001 in size - it sounds like that was what you ended up using and that seems to have done a good job.

I do hope in the future that it will not be necessary to do that, but this is a pretty sensitive area to mess around with, it's one of those things that is easy to introduce new bugs with other situations when trying to alter things to fix a different case.

- Michael