I haven't fitted greasing fittings to my carriages as it's a PITA with the 15mm Hiwin's. Can I get away with just oiling the rail and then moving the carriages a few times over the oiled area.

I bought 2nd hand Hiwin and when I first got them they were a little tight but the jig had not been moved in a long time. I added a little synthetic engine oil to the rails and ran the carriages a few times over the oil and because super silky smooth like my clone rail is (Clone rail and carriages were new). I also realised I'll have to strip it down to add greasing points so oiling the rail would save me a lot of hassle.