Tony Cox wrote:
: After flying around for an hour or so to warm it up before draining,
: I happened to notice that oil on the dip-stick is 'beading', rather
: like raindrops on a window pane.

You're probably seeing some water condensed on the top of the dipstick
running back down. Burning gasoline results in some water being produced,
which eventually goes out the crankcase breather. Some condenses on the
top of the dipstick because it's probably the coolest point in the engine.

: Am I right in thinking that this oil has wetting additives that have
: boiled off in use?

I don't think it has such ingredients. Oil wets metal very well without
any assistance.
--
Aaron Coolidge