Investigation: downsides of being generic and correct

[Dicebot]

Want to bring into discussion people that are not on Google+. 
Samuel recently has posted there some simple experiments with 
bioinformatics and bad performance of Phobos-based snippet has 
surprised me.

I did explore issue a bit and reported results in a blog post 
(snippets are really small and simple) : 
http://dicebot.blogspot.com/2013/05/short-performance-tuning-story.html

One open question remains though - can D/Phobos do better here? 
Can some changes be done to Phobos functions in question to 
improve performance or creating bioinformatics-specialized 
library is only practical solution?