From my perspective, it is legalistic because it both takes away and adds to the Scripture in the name of following Scripture.
Great point, Pastor Randy.
Iron does indeed 'sharpen iron'. But when teaching becomes "doctrine" or (worse still, arguably) the "traditions of men", and then eventually "law", there is a problem.
I contend that this is why YHVH charged Adam with the rule over his own house, and that when a man "abdicates" that Authority, even with the best of intentions, to any other earthly "master", he has submitted himself to obey "another master".
We can learn from many teachers - even those with whom we have substantial disagreement on many aspects of Scripture. But the responsibility for the CHOICES made rest with the man to whom He has given Authority (Gen. 3:16, Numbers 30:15, Joshua 24:15, etc. -- up to the three witnesses in Matt. 22:21, Mark 12:17, Luke 20:25, and so on...)
Blessings,
Mark