Experimentally inspired parametrization ("effective")

• σ(gg) ⋅ BR(WW)
• σ(VBF) / σ(gg)
• BR(γγ) / BR(WW)
• BR(bb) / BR(WW)

• σ(WH) / σ(VBF)
• σ(WH) / σ(ZH)
• BR(ZZ) / BR(WW)

• BR(ττ) / BR(bb)

SM-inspired parametrization ("fundamental")

The exhaustive list of degrees of freedom (as far as I can tell) is:

• g_W, g_Z, g_b, and g_τ
  • Closely related to the experimental outcome (in varying degrees).
  • g_W and g_Z are linked via SU(2).
  • g_b and g_τ are linked via fermion symmetries.

• g_top
  • Not so closely related to the experimental outcome.

• Total width
  • Likely only an upper limit if the width is the SM one.
  • Sets limits on invisible width if we assume g_charm.

• g_charm
  • Undetected; requires an assumption in every case.
  • Linked with other fermions
  • When g_b and g_τ are released, lump it up with an invisible/undetectable width?

• BSM "plugins"
  • allowance for new particles in the gluon/gamma loops (2 parameters)
  • allowance for invisible width (1 parameter) (but 100% anti-correlated with g_charm assumption)