[sdiy] Op Amp Buffer stability

[David G. Dixon]

> It's not an either - or.
> Putting a cap on the divider filters the reference, and goes without
> saying / should always be done.

Oops!  I guess it 'doesn't' go without saying, because I've never done it.

However, if I have a pair of 10uF electrolytics on the rails just downstream
of the power connector, do I then also have to filter the rails again at any
reference dividers?  I would have thought that one pair of big decoupling
caps on a board was enough.