You should feel it more then see the difference. The best and safest way is to practice on the track and try this. Really lean the bike into a corner and start tapping the brake (Carefully) your gonna notice it carve more into the corner then if your just leaning.
Now your first instinct from racing is that if you let off the throttle in a corner the bike wants to stand up. It is quite opposite when braking, even tho the bike is slowing down braking allows the tire and suspension to compress and creates more sidewall patch which causes the bike to steer into the corner and not stand up.
The only way to gauge yourself is start paying attention to braking cones on the track, use these cones as guides to how soon your braking and use that braking to turn instead of slowing down then turning. Slowly start taking corners hotter(Braking late) just do it in moderation so you don't over shoot a corner. Play with the brake as your taking corners on the track get a feel for what it does when the bike is laid over.
Now the hotter you come into a corner the more brake pressure you apply to carve the bike, so FEATHERING is just another way of saying don't keep the same pressure applied once you commit to the corner even tho it still might be hard pressure.
Hope i didn't lose ya lol it can be confusing i didn't pick it up until i just started noticing myself doing it once i came into corners hotter.
Trail Braking is DEFINITELY not something you do on the street

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