I believe that is incorrect , for the most part nowadays auto works well , not saying you won't occasionally run into a nic that doesn't play right but it's fairly rare now . Just make sure both ends match , switch = auto then the nic "must" be auto also . If your network is any size at all trying to hardcode everything is really not scalable , it involves too much work. I would hardcode any server connections. Below is blurb right out of a cisco best practices doc.
Recommended Port Configuration (Autonegotiation or Manual Configuration)
There are many opinions on the subject of autonegotiation. Previously, many engineers advised customers not to use autonegotiation with any switch-connected device. However, improvements in the interoperation of autonegotiation and the maturity of the technology has recently changed the view of using autonegotiation. In addition, performance issues due to duplex mismatches, caused by the manual setting of speed and duplex on only one link partner, have become more common. Because of these recent issues, the use of autonegotiation is regarded as a valid practice.
