@stephenrkell @cfbolz @wingo Many years ago I wrote a blog post on the downsides of tail calls on debugging https://tratt.net/laurie/blog/2004/tail_call_optimization.html only to discover later that at least one paper (Smith and Ungar, cited at the end in an update) had also alluded to the problem. I've sometimes wondered: how soon after tail calls were introduced did the debugging downsides become known?