Rethinking FDGRX allocation

[roomtempmayo]

For about the last seven or eight years, I've been 40-50% in Fidelity's Growth Company Fund: https://fundresearch.fidelity.com/mutual-funds/summary/316200104

Over the last decade, it's earned its relatively high fees (0.83%) by outperforming VITSX 22.77% to 14.71%.

However, YTD FDGRX is only just barely earning its fee premium over VITSX by returning 19.99% to VTSIX's 18.43%.

So far, I've stayed heavily in FDGRX simply because it's worked, not because I have confidence that it will always outperform VITSX. 

How would you assess the relative weight you'd have in these two funds?

[TheYeti]

The Asset Correlation of the 2 funds is .92 via portfolio visualizer. So they are 92% similar. I prefer index funds for the low fees and am very comfortable with the total market index fund. You did not say if the investment was in a Tax deferred or Brokerage account. If it was in Tax-deferred, I would switch it all to the index fund. If it is in brokerage, it is not worth the capital gains to switch, leave it alone and put any additional funds into the index fund.