Whether the taxpayer could deduct January-September family living costs and obtain a more favorable tariff despite separation during 2010.
No. Living costs are non-deductible personal expenses, and the applicable tariff depends on the marital/family status at year-end.
For annual postnumerando taxation, the year-end status on 31 December governs both separate/joint taxation and the applicable tariff and social deductions. The claimed living costs are expressly non-deductible.