Nudging through advance ground rules

A client under stress rarely makes their best decision in the moment. The workbook's answer is to make the decision before the stress arrives.

Laying down advance ground rules that the client buys into gives an adviser a built-in nudge the client already agreed to follow. A rule on when to rebalance an asset allocation, set calmly in advance, becomes an automatic prompt to book profit when prices are high and to buy when prices are low. These are the two things clients find hardest to do in real time.

The mechanism has three parts:

1. Agree the rule in advance, while the client is calm and thinking long term, not during a market swing.
2. Attach the rule to a trigger, such as an asset class drifting away from its target weight in the portfolio.
3. Let the rule, not the mood of the day, decide the action. Rebalancing back to target automatically sells some of what has risen and buys some of what has fallen.

This is the same idea the workbook uses elsewhere in the chapter: a pre-decided asset allocation policy with upper limits for each asset class stops overexposure to one class after it has run up, and a maximum exposure limit within an asset class does the same for a single security. Both are ground rules agreed in advance, doing the client's risk management for them at the exact moment their judgement is least reliable.

Mr Bose sets a target allocation of 60% equity and 40% debt, with an advance rule: rebalance whenever equity drifts more than 5 percentage points from target.

A strong equity rally takes his portfolio to 68% equity and 32% debt on a corpus of Rs 50,00,000, which is Rs 34,00,000 in equity against a Rs 30,00,000 target. The advance rule triggers automatically: sell Rs 4,00,000 of equity, move it to debt, and the portfolio is back to 60:40.

Without the rule, Mr Bose, feeling good about the rally, might instead have wanted to add more to equity at the top. The ground rule agreed months earlier, when he was calm, overrides the impulse he feels now that he is not.

Chapter 17, section 17.2 'Nudging the investor to behave better', states the rebalancing example directly. It sits between the discussion of emotional biases in section 17.1 and the adviser's role in managing client emotions in section 17.3, so expect it tested as the practical technique that answers the biases described just before it, particularly chasing past performance and overconfidence.

• The nudge only works if it is agreed in advance. A rule proposed during a market swing is not a ground rule; it is just another emotional decision.
• Rebalancing under this rule can mean selling a winner, which feels wrong to most clients in the moment. That discomfort is exactly what the advance agreement is designed to override.
• Do not confuse this with dynamic asset allocation, which uses pre-defined models to remove the subjective element entirely. Nudging through ground rules still involves the client's own agreed choice, just made ahead of time.
• The technique targets behaviour, not returns. The workbook does not claim it improves performance, only that it removes a source of bad, emotion-driven timing.