Ciuld we ever see joint operation of any routes? For example, the X26, sorry SL7, could be operated by RATP or Metroline from the Heathrow end, and GoAhead from Croydon.
Never say never, but unlikely under the present arrangements. A Route Contract is awarded to one operator, who accepts the conditions applying, such as EWT (Excess Waiting Time) targets, operated mileage targets, and so on (there are very many such conditions and targets to be met!). For some form of joint (operator) operation, there would need to be two individual such contracts, specifying which trips were included. If the route failed to meet overall performance targets, how would the penalties be apportioned?
There is also the slight problem that, under the London tendering system, individual operators are not "permitted" to discuss tenders with each other. Of course such conversations (at a very high level . . . or at a very informal level) do take place, but never admitted! To co-operate in such a formal way would, again, not be impossible, but . . .
It
would be possible for one operator to specify two Garages to work on the route, as the operator would still hold the contract and be responsible for any penalties. It would then be down to the operator to manage the operational performance between the Garages involved. It is
very rare, but not unknown . . .
Historically, having two garages on one route was fraught with problems . . . crews would "punch up" (closely follow) crews from another garage to reduce their workload; would engineer a breakdown if the following crew was from another garage and then, having rectified the "problem", then punch up the other crew! It was actually quite rare for crews to have a break at a "foreign" canteen; although Country crews were much more easy-going . . . driving each others' buses and having breaks wherever there was a canteen.
London bus routes generally don't run far from their operating Garage, so the need seldom arises. As I say, not impossible, but very unlikely . . .