Sub-Object Named Selection Sets in Editable Poly are lost in many cases. This should not happen. Instead, the named selection sets should survive new modifiers as well as using Collapse To in the modify tab.
In the case of adding modifiers: a named selection set should be available up the stack in the same way that sub-object selections get passed up the stack. This would mean that in the case of topology changes, the named selection set should adapt. For example, if a named selection "Polys1to10" set on Polygons 1..10 are set and a Tessellate modifier is added, the named Selection set "Polys1to10" would be all the resulting polys of that modification.