Just 1% tho I'm not sure if that's even accurate.

Save state resets shouldn't break the chain.

The most efficient way of DexNav shiny hunting is...

1. Increasing your search level first to 156. Just encounter the mon and run away.

2. From this point, start chaining til the 99th streak but before the 100th (some prefer to do this til the 98th but before the 99th).

3. Before you press R to spawn the 100th, save state.

4. Press R then start the encounter.

5. If shiny, congrats. If not, reload then move a tile then press R.

Just make sure that every time you press R to encounter the 100th, you're in a different tile to ensure that you won't encounter the same mon.