Just shortening some Xt brake hoses and refitting as per http://techdocs.shimano.com/media/techdocs/content/cycle/SI/SI_8JA0A/SI-8JA0A-003-00-ENG_v1_m56577569830750008.PDF
It is very specific about the position of the olive when re inserting the hose into the brake lever, 2mm from the end, but the olive is completely loose on the hose and can just slide around where it wants as you slide it into the lever.
Should it be tight on the hose beforehand? I can't see how it can be until squashed down when you tighten the nut. I've done it and it all seems to work fine, but will/should I just be thinking about that 2mm when I'm caning it down towards something nasty?