nah its not that I was talking about. Its in the same category with Slide vertices and edges in Blender. In Max there is also face and normal constraint besides Edge constraint. Very useful when you dont want to ruin your curvature. Here is the video
I wonder how you guys deal with preserving your surface shape curvature when moving components around because vertex slide isnt enough in many cases. Recently there was a Set Flow addon It is finally here... EDGE FLOW (SET FLOW) for Blender ! (Benjamin Saunder) . I dont know how someone can do subd modeling without these as well.