Why do they have to be separate then at all?
Anyway, you could do this but its unproductive for your uderstanding of do's and donts. I mean just go to the groups trasform and tick show selection handle. then you can select BOTH each individual thing and the group.
Else just omit the extra transforms and put the shapes under the transforms. This omits the problem AND it does not realy on events trigering and inevitabluyy not working the way you want.
Like i said theres no such thing as a group in maya, nor a an object
I mean:
CODE
// Think of theese as placeholders for
// your paperclip.
file -f -new;
polyCylinder -r 1 -h 2 -sx 20 -sy 1 -sz 1 -ax 0 1 0 -rcp 0 -cuv 3 -ch 1 -n "hires";
polyCylinder -r 1 -h 2 -sx 12 -sy 1 -sz 1 -ax 0 1 0 -rcp 0 -cuv 3 -ch 1 -n "medres";
polyCylinder -r 1 -h 2 -sx 8 -sy 1 -sz 1 -ax 0 1 0 -rcp 0 -cuv 3 -ch 1 -n "lores";
createNode -n "allObject" transform;
parent -add -shape loresShape allObject;
parent -add -shape medresShape allObject;
parent -add -shape hiresShape allObject;
//delete the original trasforms
//shapes will remain in allres
delete lores medres hires;
//then add the switching there.
Or use nurbs then you automatically get lod with one shape.
So no dont think "make one thing select other", its counter productive, but think make one thing other. So while the counter productive is common way of thinking theres better ways tro soleve things that t ask that question. So it is a bad solution for what you really want.