I guess so because His program can utilise Multiple GPUs where as bitcrack can only use 1 at a time. And for the guy posing the WIFsolver CUDA does it work with multiple GPUs.
You may always split the work. The same with BitCrack. There is even option to use the specified part of given range - so you may launch 8 instances with the same configuration and then specify for each device to process 1/8, 2/8, 7/8 of the range... I think I will add something like that to my program, good idea.