If you’re going to use anything heavy like motor oil, be very careful to wipe any residue off before you start clipping - the last thing you need is a glob of that heavy oil getting in your calf’s hair, especially if you’re fitting. The heavier oil is no doubt better for the life of your clipper blades, but mere convenience isn’t the only reason most fitters use final bloom (or something similar). Whatever you use for lube, get yourself a small soft brush to clean your clippers, and use it regularly - especially when you’re clipping in adhesives.
I like the little bottle of oil that comes with the Andes clippers - I use it when I start and when I stop, but again - being sure to wipe away residue. But when i’m fitting, especially like a leg, I use a quick shot of final bloom regularly. As long as you don’t overdo it, it won’t break down your adhesive but your blades will cut much better and smoother. Be sure when you spray it on your blades the overspray isn’t hitting the leg.