[seanhunter]

Not the OP, however I have programmed in C++ since 1987 across many different operating systems and hardware platforms and I've literally never heard of a compiler that implements template stuff using runtime dispatch. CFront3 which was I think the first real template implementation that most people used certainly never did it that way, neither did any version of gcc, visual studio or Sun Workshop, which are the compliers I used the most from that period. Dug out my old copy of Coplien[1] which is from the early 90s and it discusses runtime dispatch in depth in the context of vtables and virtual function pointers and the cost of these things, so the concept was well understood but not a cost anyone was paying with templates.

[1] https://archive.org/details/advancedcbsprogr00copl "Advanced C++ Programming Styles and Idioms" aka the first programming book that genuinely kicked my ass when I first read it and made me realise how good it was possible to be at computer science.