That's similar to what I did. I have one (Roth IRA is a target 2020) that's aimed at age 63, and another (Rollover IRA is a target 2030) that aims at age 73. The 2020 is about 77% stock, while the 2030 is about 87% stock. All things considered, I'm quite comfortable with those percentages.
This is similar to what I am considering... but perhaps for different purposes.
I want late life allocations on auto-pilot (since DW does not/has no interest in managing the portfolio).
Plus, I believe it is easier for me to manage the expense budget and income in 10 year intervals rather than in perpetuity... I can get my mind around it.
My general plan is to get appropriate growth for the future decades and preserve capital in the near decades. Of course, we are factoring in SS and pensions. I see it like this starting @ 55 in 2012:
55 - 65: Slice/Dice (Mutual funds) The allocation for this 10 years is (20/80 - S/B). (with about 10 years of income in fixed assets 80%... this amount + pension would give us a good retirement income) The fixed assets
will not be rebalanced to the stock portion (20% in stocks with no new money added to stocks). All stock dividends go to the cash account (same with bond dividends and any forced cap gain payout form the mutual fund). The goal on the stock allocation is to drain it into fixed assets on an opportunistic basis based on growth with a target to taper down to 0%. The total amount in this decade is generous and could have about 10% left over for the next decade (depending on actual spending and stock growth). This is about 40% of the entire beginning portfolio (not including House)
65 - 75: A target fund (year 2025) with a projection of having 10 years of income needs provided. This is about 35% of the beginning portfolio
75 - 85: A target fund (year 2035) with a projection of having 10 years of income needs provided. This is about 18% of the beginning portfolio.
85 - 95: A target fund (year 2045) with a projection of having 10 years of income needs provided. This is about 7% of the beginning portfolio. Statistically at least one of us is likely to be gone. The house is likely to be sold and proceeds used for living expenses, medical needs, etc.
95 - 105: Any spillover for the previous decades... If one of us lives this long...
I am still playing with the % of the portfolio allocated for the later 3 decades. Plus, we would make common sense adjustments in spending if adverse conditions arise. We cannot predict the future... if one of us dies early or experiences very serious health problems... we will adjust.
Anyway... That is how I see the TR funds helping us. Auto-rebalancing for future decades of funding.