Sion Vs Stuns

I get that getting stunned halts Sion's axe, but can he either complete the swing after the stun ends or at least not have the ability on cool down for so long after? I'm sure the reduced cool down of 2 seconds is supposed to be a mercy, but it actually feels the opponent got to temporarily silence your main ability in addition to stopping it after you have to baltantly telegraph for 1-2 seconds. It is worst against teams that do it multiple times in a row and you walk out realizing you did nothing the entire fight but put up your shield and yell at Tibbers