Detail Components Best Practice for Reference Planes

[Jonathan_Drachenberg]

I know it is best practice to always constrain model geometry to reference planes - however, when building detail components, is it important for 2D linework to also always be constrained to reference planes? If so, why?

For example, in a family like the one below, is there any reason to offset all of these reference planes 2mm so that all of the inner linework can also be constrained to reference planes? Would it potentially cause any performance issues if I simply lock dimensions from the reference planes I have already drawn to the linework itself rather than a reference plane?

Thanks for your help!

[barthbradley]

Is it parametric?  If not, the reference planes are frankly unnecessary, unless you need more references to snap to (e.g. "Is Reference" equals something other that "Not a Reference").  Even then, "Is-Reference" RPs separated only by 2mm could be more a nuisance than a help.  I would have 2 at minimum that establish the x,y Origin (e.g. Insertion Point). 

[ToanDN · Accepted solution]

No.  You can place dimensions directly to linework and assign parameters to them or lock them.  However you do need ref planes / ref lines if you need to stretch the family in the project, or you need center references for dimension graphics.

[Jonathan_Drachenberg]

Thank you!

[Jonathan_Drachenberg]

Yes, it will be parametric.