This is probably completely and utterly wrong as it's just a guess, but potentially the Thumb [1] instructions (small, limited subset of shorter instructions in ARM) might allow for a wider setup. Thumb instructions make a bunch of simplifying assumptions that might remove some of the issues with going wider. Not that I have any idea if Cyclone even supports them in the first place.
The biggest wart on the ARM instruction set was the predicate attached to basically every instruction. That's gone in the 64-bit ARM ISA, so there's no need for a 64-bit Thumb (and there isn't one).
[1] http://en.wikipedia.org/wiki/ARM_architecture#Thumb