If we want to improve the inner London train service, it has to be done at the point that franchises are renewed / awarded. There is always a bun fight between inner London areas, which would like to see more frequency - and outer London / out of London commuters who want fast trains that don't make too many stops. The train operators themselves support the latter group, because that's were most of the money is. They comply with the minimum standards as mandated in their franchise agreements and no more. If there are short term decisions to be made about which of the two suffer as the result of delays and capacity problems, and where they have more 'wiggle room' invariably it is the inner London services that feel the pain. If we want to change this, then we need as many sections of London rail as possible to be taken over by Transport for London / transferred to the overground network. In the longer term, the best solution is to get a dedicated, high frequency, London focussed service (aka 'the tube).