In most cases probably not. My entire layout was built with Gargraves flex. I did read up on using easements. Didn’t really understand all the math and such involved. I made a jig to bend the track to a 072curve. Then basically bent it back to somewhat of an easement just by simply eyeing it.
I now run body mounted Kadee’s on even my 21” passenger cars. With an easement they negotiate my 180 curves just fine. One area that went from a straight portion to a fixed 072 curve. I had an instant derailment. It has since been changed. These cars can handle 072 curves. But they do seem to need a gradual turn before they see a true 072 curve.
