I don't have Hale's book to hand, but I suspect you've misquoted him about 'age in bonds'. Bonds fluctuate in value less than equities. Does it matter to someone aged 90 who has £5M in equities to cover £5k expenses per year to have all equities? Of course not; you have to apply 'rules of thumb' with some common sense; they're a starting point for thinking, not the end solution.
Investing in bond funds is best done with an understanding of the risks. Hang on, that applies to anything.....Bond/fund risks are: credit (they default); duration (the longer, the further the value falls when interest rates rise); inflation if they're not linkers; currency with unhedged foreign bonds.
You can't do much about the first beyond sticking with stable governments, but you can do a lot about the second, and you should duration match your spending with the fund(s)' duration. All the hand wringing about an unprecedented bond rout in 2022 could have been avoided with duration matching our bond investments, which is how you minimise duration risk with bonds; which means you'll miss the big gains possible, but you shouldn't be hit hard by the big falls. Sounds familiar with investing. The only surprise in 2022 should have been that interest rates could rise so quickly, so much; but where was the regulation or theorem that that couldn't happen?
The interest rate on linkers can't be derisory compared to the interest rate on nominal bonds. Any time the return on one investment is better than another, assuming risk is similar, money will move from the derisory return investment to the non-derisory return investment until both returns are about the same. Some of us are right to stay away from bonds.
Global stocks have returned about 4.9%/year real over the last 30 years. Any carefully chosen IT that gives 4%/year or more in dividends and has the prospect of matching inflation of 2.5%/year is going to be doing unrealistically well I'd suggest.
Bonds have beaten stocks over longer terms, 10+ was mentioned. Less often the reverse happens: 2000 to 2016 US investment grade bonds beat US stocks, with much less volatility. Why wouldn't that happen again, and is 16 years some limit?`
The idea that for retirement income equities should be dividend focussed to reduce the sequence of returns risk has been repeatedly challenged as the 'dividend fallacy'. Read an explanation here to make up your own mind
https://www.evidenceinvestor.com/confus ... dividends/ Hale warns about short term patterns, correctly. But if it takes 100 years to establish a reliable pattern, will you be investing for 100 years to benefit from knowing the pattern? Worse yet, if there are actually three distinct 100 year patterns we are part the way working through, what use is knowing one of those patterns? Look at the past, but be careful concluding what it suggests about the future.
i think my luck does not work that way.