Question about NNUE: Why is L2 = 15 and not 16?

[octopus-prime]

A very naive question about the nnue network...

constexpr int       L2Big                           = 15;
constexpr int       L2Small                           = 15;

    static constexpr int       FC_0_OUTPUTS                 = L2;

    Layers::SqrClippedReLU<FC_0_OUTPUTS + 1>                                           ac_sqr_0;
    Layers::ClippedReLU<FC_0_OUTPUTS + 1>                                              ac_0;
    Layers::AffineTransform<FC_0_OUTPUTS * 2, FC_1_OUTPUTS>                            fc_1;

Why L2 is not just 16? Should be perfect for simd...
And 2 * 15 = 30 and not 32. Seems again not perfect for simd.

So why it has to be 15?

[cj5716]

an additional skipped connection as part of #3927

[octopus-prime]

Thanks