The Decision Framework Crutch
Pre-decide hard rules so future-you can't sabotage current-you
Matthew argues humans are wired for fight-or-flight, not multi-decade decisions. The fix is to pre-build hard rules — what he calls decision crutches — that define when and how you'll act, so the in-the-moment emotional brain has no authority to override them.
The canonical example comes from behavioral finance researcher Greg Davies, who refuses to make any investing decision on a weekday surrounded by red market screens. He only decides on Sunday mornings with a coffee, in calm conditions. The rule isn't a preference — it's binding.
The framework works because it moves the decision from when you're triggered to when you're regulated. You decide once, in advance, what conditions are required for any high-stakes choice. Future-you, mid-panic or mid-euphoria, no longer has authority.
- Decisions made under emotional load are systematically worse than decisions made calmly.
- Pre-committed rules are stronger than willpower in the moment.
- The cost of waiting half an hour before acting is almost always lower than the cost of acting impulsively.
- Self-knowledge of your trigger conditions is the foundation of every good rule.
- Hard rules only work if they're binding — soft preferences collapse under pressure.
- Identify a past decision you regretRecall a financial decision you wish you hadn't made. Reconstruct the conditions: time of day, mood, what you'd just read or seen, who you'd just spoken to. Patterns will emerge.Pro tipLook for repeated triggers across multiple regrets — those are the high-leverage rules to build.
- Name the trigger conditions explicitlyWrite down what state you were in. Friday evening after a hard week. After a few drinks. After a winning bet. After a market drop. Triggers can be negative or positive — euphoria is as dangerous as fear.WarningDon't only watch for negative emotions — overconfidence after a gain is equally lethal.
- Write a hard rule that blocks those conditionsConvert the trigger into a binding rule. 'I will not make investment decisions on weekdays during market hours.' 'I will not place a trade after a drink.' The rule must be specific enough to be unambiguously broken or kept.Pro tipUse absolute language — 'never' and 'only' beat 'try to' and 'usually'.
- Insert mandatory frictionBuild a delay between trigger and action. Even 30 minutes of pause is often enough to engage higher-order thinking. Account locks, withdrawal penalties, or a written checklist can all serve.Pro tipLifetime ISAs and similar penalty-on-exit accounts function as built-in friction.
- Define the calm conditions for real decisionsSpecify when you ARE allowed to decide. Sunday morning, coffee in hand, no screens, no recent news. The positive frame — 'I decide here' — is as important as the negative — 'I don't decide there'.
- Test the rule against a real triggerWait for your next emotional spike — a market drop, a hot tip, a bonus — and see whether the rule held. If it didn't, the rule is too soft or the friction is too low.
The Oxford Risk behavioral finance expert is surrounded daily by red market screens. He pre-committed to making investment decisions only on Sunday mornings with coffee, away from screens.
When COVID dropped markets 20%+, Demo wanted to dump his cancelled property deposit in immediately. Instead, his investor group agreed to one Sunday-scheduled buy per week over 20 weeks.
Demo describes winning £50 on Chelsea, then betting on Liverpool, then by 7pm betting on Turkish league 15 football having lost £500.
Matthew watched clients with 30 years of investing experience still freak out during market corrections, despite knowing the data. He realized objective truths only become real when your own money is on the line, and that no amount of education substitutes for pre-committed rules.
He credits Greg Davies of Oxford Risk for the sharpest version: a behavioral finance expert who deliberately removes himself from screen-induced bias by limiting investment decisions to calm, off-market hours.