Clapham Junction → 1.7 miles → Wandsworth Road → 0.4 miles → Clapham High Street → 2 miles → Denmark Hill → 0.9 miles → Peckham Rye → 0.6 miles → Queens Road Peckham → 1.5 miles → Surrey Quays
That's six gaps, half of which are 1½ miles or more. In comparison, on the Overground between Willesden Junction and Stratford there are 17 gaps, none of which are over 1½ miles, and only one of which is over a mile.
The longest of these gaps - the dash through Brixton - has been in existence for decades. But the two other long gaps will be created this weekend as a consequence of diverting the ends of the South London line to create the Overground. Residents of East Battersea will have to walk further to get a better service. Meanwhile the decision not to build a station at Surrey Canal Road means locals will now find fewer trains on their doorstep, not more. And OK, so none of these long gaps are insurmountable on foot, and London doesn't have a bottomless transport budget. But if you want to create a truly accessible rail network, it helps if your trains stop regularly along the way.