>If you won't take it at my word that "computer doing a worksheet's of calculations automatically" is faster & less error-prone than "a human [with electronic calculator] doing that by hand", then that's a you problem.

Reality is complicated and messy. There are many hurdles to overcome, many people to convince and many logistics to handle. You can't just replace accountants with computers - it takes time. You can understand why I find it hard to believe that a huge jump like the one with software can take time as well.