The dividend yield columns in the optimizer show different yield values.
This is because the optimized annualised yield takes account of the timing of dividend payments.
Consider the three dividend tab
Dividend yield simply adds up the three dividends and expresses them as a percentage of the current share price.
Anualised yield will take account of the number of days to realise the three dividend payments and so will always be lower than the Dividend yield. It is the annualised yield that is the important calculation because it takes account of the number of days. Rather like an APR.
As an ex dividend date draws near, the annualised yield and the dividend yield will converge and on the day before going Ex-dividend will be almost identical.
Consider the two dividend tab
Here, the opposite is true to the three dividend tab. Because of the timing of the dividends, the Annualised yield will always be higher than the actual yield. That is because the two dividends are always spread over a number of days that is less than 365 and as you get closer and closer to the ex dividend date, this yield will always be rising relative to the Dividend yield.