Ross, if you need contact at one or more points to achieve a perfect, full length cut of a sheet of paper, either your bedknife is not precisely straight or your reel is not precisely cylindrical, along its full length. If the problem is very slight, it can probably be cured by back-lapping rather than a full resharpen, but I personally do not approve of backlapping to deal with a problem of more than a few ten-thousandths of an inch. However we have some greenkeepers here who disagree with me quite vehemently, so I won't claim that I'm right.
