There are 2 syslinux.cfg files, 1 for BIOS and 1 for UEFI. I do forghet that some time and edit the wrong one on my UEFI boxes. The reason i do edit them is that i have at least 2 LE versions on my box (stable, nightly) and select with the help of menu.c32 or vesamenu.c32.
My solution is the UEFI one just includes the BIOS one.
/flash/syslinux.cfg normal as ever
/flash/EFI/BOOT/syslinux.cfg only with one line "INCLUDE /syslinux.cfg"
That works perfect for me. But at least in packages/sysutils/busybox/scripts/init and the getedid tool the syslinux.cfg is manipulated and copied.
Thanks for reading my proposal