A fair amount of EMO owners have already discussed this on the forum.
Yes, that is correct, when EMO dances his feet sensors are unable to detect edges. So it would be recommended to keep an eye on EMO when he is dancing, or place him in a safe play area so that he will not fall / topple over when he does dance.
Recommended to create a safe play area with approx 3.5 cm high border as sometimes he can lift his leg/foot up pretty high 
You can check out this old thread where EMO owners are discussing EMO playground ideas
