In some boilers the minimum can be as short as 600mm now, but yes he should be fitting copper direct to boiler.
Also would have to question the use of 15mm for main flow and return, surely a 22mm pipe with 10mm connections from manifolds would be better for efficiency.
Although having re...
this is the nut that keego is meaning...hope this helps
http://i642.photobucket.com/albums/uu142/chabawas/IMG1156_2.jpg
also in case you didn't know please be sure to isolate the water supply first, sorry to sound patronising but sometimes things like this don't occur to some folk.