Quoting the talk, very quickly...
Which command outputs \\?
echo "\\\"
echo "\\\\"
echo "\\\\\\"
Which of those gives you a string with two backslashes in those other languages? Exactly the same one as (ba)sh.
"${*##*[ ]}" is a valid POSIX approach to getting the last parameter but it doesn't work in ksh or bash. Those shells apply the pattern to each parameter in turn when used on '*' or '@'.
That text is from a developer who has profound depth.
A portable method to extract the last argument is:
for last
do :
done
More importantly, the difficulties humans have with the language are different from the difficulties computers do, and I was mostly thinking about the latter, what with the mention of LR parsing and everything.