if you started the turn to follow the SID and then engine fails what you should do
In the ideal world, your company will have done the sums and your OM published procedures will address any reasonably likely eventuality .. ie follow the procedure should be the mantra.
The reality is that some operators don't do what they should and the crew (and pax) are left between a rock and a hard place in the event of an awkward failure.
Either you do have the sums done and a suitable procedure or you are trying to wing it.
Which alternative would you prefer to argue at the enquiry after the accident ?