Ahhh ok, see your point- lol.
I have al ittle girl so luckily this problen has not cropped up, I just chop her fringe whenever it starts poking her in the eyes!!
How about cutting it over the course of say a weekend or a couple of days when you're not going out? For example, chop a bit off on Friday night, bit on Saturday and tidy it up on a Sunday....that way you're only doing it in short bursts?
Or....how about when he's in his chair eating? Give him a slice of toast, stick CBeebies on so he's distracted and do it then???