[g19fanatic]

thats still pretty easy in blender, just takes a different approach! Goto edit mode in the part, goto vertex mode, wireframe view, select all of the vertexs for the hole on both sides of the solid part, then move then (in the right selection mode) in the proper direction using your keyboard to move the exact amount needed. Depending on the specifics needed, you can setup custom axis and such to move them anywhere needed (lets say you needed the hole .5mm but 45deg from the current one ref'd from a specific edge).

The same thing can be said for resizing whole faces, moving parts, etc... Its all possible and usually pretty easy to do, just takes a different mentality from that of a parametric modeller.