If you are using Turbotax standard version or any other paid version, the split pension is automatically optimized unless you want to change the transferred amount. This calculation is not optimized in the free version.
Line O is the tax deducted from the Pension eligible to transfer which is the amount you used in Line E.
This is a link on how the split pension optimizer work:
https://turbotax.community.intuit.ca/community/pension-retirement/help/how-does-the-pension-splittin...
I hope this was helpful
