Not sure if I missed something, but clicking on Theory Lesson 1.2 Half Whole Diminished Scale comes up with “Page Not Found.” (On both iPad and Mac, both using Chrome browser)
Hey Scott 
Thanks for letting me know… I have fixed it.
Cheers,
Hayden
Thanks Hayden! I appreciate how you’re always on top of whatever problem comes along.
It was a year ago (October 3) that I came across PianoGroove. I’ve a long way to go, but it’s really remarkable the advances I’ve made so far. You–along with Tuomo, Jovino, and Lyndol–have created a really great place to learn. 
My pleasure Scott and that’s awesome to hear on your progress.
I think you’re going to really enjoy Robert’s jazz organ course. I’m around 50% through with the editing and it’s looking great. It ties in beautifully with the rest of the content on PianoGroove.
Walking bass lines and rootless harmony are both essential to play jazz organ.
All of Robert’s course focuses on F Blues, so perhaps refresh yourself with Tuomo’s lesson here on walking bass in F Blues:
The form that Robert uses is the jazz blues progression which you can learn about here:
and of course the theory lessons in our course on rootless harmony is essential:
That will get you well prepared for the organ course.
I’m confident I can get the course edited and uploaded this month. More updates to follow.
Cheers!