Hello,

An additional thought on the placement of this basal keiki: I looked at this
orchid again, and with all the aerial roots, I wonder whether as far as the
plant is concerned that is the base of the plant now. The two leaves below
that level are still green, but if they grow yellow by the next time this
plant needs repotting (probably still a while from now), I will repot it so
that the media reach that point.

It's hard to say how leaf number and position affections the local
hormonal concentrations....it could be just that the plant is prone to
making keiki there for whatever reason(s). With my Phal (Buena Jewel X
Coral Isles) which I don't think has an official RHS grex yet, the
'basal' keiki was made below the very top leaf. There were 4 leaves
below it at the time! What's your phal called? Maybe they share
similar genetic makeups?? Mine actually started out on what I thought
would be a flower spike, but when it grew about a centimeter, it shot
out a tiny leaf...it's working on the second leaf nowadays. But hey,
there's no such thing as a bad keiki, so I say, enjoy it.

This reminds me of the orchid grower whom I encountered in Wisconsin who
would always cut off perfectly healthy leaves below the highest aerial root
and repot his Phals so that all aerial roots were in the pot -- very unusual
fellow in many ways, and an orchid hybridizer with decades of experience so
this was not due to lack of knowledge but just eccentricity I guess. Also a
coworker of mine (who is an orchid newbie) asked me recently (talking about
aerial roots) "What are those ugly things that look like worms that are
coming out of my orchid, and can I cut them off?" I guess people's aesthetic
tastes differ greatly. Personally I am quite fond of aerial roots, the more
the merrier.

Yeah I've heard of the whole leaf sacrificing behaviour too.
Personally, I never understood it, and would never do it myself. And I
too agree with you on the matter of aerial roots - the more the better I
say. Besides, those are the only roots that I could never kill by over
watering, ha!

Cheers,
Xi