There is no tax on investment distributions while held in registered accounts.
Tax is deferred until withdrawals are made at which time, 100% of the withdrawal is taxed as regular income at the account holder's marginal tax rate.
Since tax-efficiency is lost once a withdrawal is made, it would make sense to hold your most highly taxed investment in the account - such as interest bearing investments.
You still benefit from the original tax-deduction on contribution and tax-deferral.
If this is your only account then Account Allocation will not matter.
If you have a Non-Registered Account (NRA) and/or a Tax-Free Savings Account (TFSA), you will benefit from reallocating your investments across the accounts.