I do this too. I can also start at L if my intuition tells me the letter(s) I'm testing come after L. But that's it - I have to start at L or A. I don't know why L and not some other letter.
... a
b c d
e f g
h / i
j / k
l m n o p
q / r / s
t / u / v
w / x
y and z
It’s quite funny that, as a French native, we are all taught exactly the same song! Same pace, same tone, same elemenopy, but later in life, somehow y’all just smash tough/thorough/through/trough letters together, and we go on with our hon/hen/heim.
Why? The song actually works with French names of letters!
a b c d e f g /
h i j k l m n /
o p q r s t u /
v www x y-y z
I usually know a letter is near one of those four, but not if it is before or after, so if I am looking for P for example, I'll start with T for a bit, realize I've gone too far, and start over at L in hopes of finding it.