@WalterBright To mark at some improvement - put an entry in bugzilla that contains the motivation (you are in the best position to put it together anyway as the one arguing strong for it ;) ):

> Fake loop to prevent inlining. This function is called only rarely,  inlining results in poorer register allocation.

Add @@@BUG@@@ <issue number> marker like everywhere else in Phobos, this way we can at least unravel the hack later on (and understand that it's no longer needed).

Then this issue is then split off and can be taken care of separately.

P.S. 
As to hacks and motivation - every hack is justified, the sum of them is a net burden nevertheless. Hacks breed SACRED knowledge and a cult of priesthood who are in the know. A _priest_ knows why you need this and that hack but 99.5% of our users base would know nothing of it and can't apply these magic tricks it in their code.