Condensing Spell List in Battle

for giggles, was wondering how to do that with minimal revamping.  i wonder if tweaking my algorithm posted on 9/17 could do it (stuff between dotted lines is new):

Code:

stx $f0
cpy $f0       ; does full list index == output index?  yes, i use
             ;  this variable in a single place, because no other
             ;  easy way to compare X and Y. :/
beq noCopy    ; skip copying if so, but still advance

-----
tya
eor $f0
and #$04   ; does even/odd-ness of input index match that
           ;  of output index?
beq noColumnChange  ; branch if so

inx
inx
inx
inx     ; move one output slot forward

noColumnChange:
-----

clc
rep #$20

copyLoop:
lda ($F2),Y   ; read two spell menu bytes from original position
phy
txy
sta ($F2),Y   ; save to new position

or maybe the X and Y even/odd test should be before the X==Y test?  and we'd probably want A in 16-bit mode here.

no, i'm not suggesting that untested code should replace proven code with dual list thresholds and various optimizations built into it.

just that the +1 advancement is more apparent within that algorithm to me.  and indulging weeks-after-the-fact suggestions is alright when the method only takes 5 minutes to concoct. (yet somehow typing the rest of this post took me a good 15 minutes.  wtf?)