------
## 最终结论
```python
def can_split_average(A):
    total_sum = sum(A)
    n = len(A)
    
    # Use a set to store possible sums of subsets
    possible_sums = set()
    
    # Iterate through all possible subsets using bit manipulation
    for i in range(1, 1 << n):  # from 1 to 2^n - 1
        subset_sum = 0
        count = 0
        
        for j in range(n):
            if i & (1 << j):  # if j-th element is included in the subset
                subset_sum += A[j]
                count += 1
        
        # Check if we can find a valid average comparison
        if count > 0 and count < n:  # B and C must be non-empty
            if (total_sum - subset_sum) * count == subset_sum * (n - count):
                return True
    
    return False

# Example usage:
print(can_split_average([1,2,3,4,5,6,7,8]))  # Output: True
```