mathematical notation is not automatically suitable for programming in general, but is not automatically unsuitable.
APL was devised as a notation for algorithms, not for general math; Iverson noticed that at the time (1950s), everyone was inventing their own algorithm specification when give mathematical proof, and tried to unify that. And since it was well enough specified, someone later wrote an interpreter, and that's how APL came to be more than notation. I urge everyone to read Iverson's "notation as a tool of thought".
> Best tool for the job et al.
Best tool depends on context. No programming language is the best tool if the person reading/writing/mainting it does not know the basics of how to program.
APL is suitable for programming in general for people who take the time to learn it, and is often the best tool for the job, as long as the context is "to be read/maintained by other people who know APL". IMHO, this is an unfortunately rare context.
You'd be surprised. Mathematical proofs contain lots of "english prose".
>Yet, I challenge you to back up your statement about character counting by showing me a Computer Scientist and a Software Engineer who no longer writes or uses traditional mathematical notation for anything, but has systematically moved over to the more intuitive and natural programming language of their choice, such as Scheme, C, or Haskell.
That's irrelevant. Best tool for the job et al.
>APL is a suitable replacement for Mathematical notation and was designed as such.
That doesn't make it suitable for programming in general.
And mathematical notation is much richer than APL, it's not constrained by mere sequential characters on a line.