SMRT will have bendies still for another few years. It can fix
problems one at a time. First bring in DDs for long haul routes and
cash on them such as 106, 188, 190, 851, 854, 857. Then use bendies
for routes right now that have height restriction. Use a mix of
bendies and DDs for feeder / intra-towns to see how the mix
of bendies and DDs are coping with the load.
Slowly try a few routes with DDs only and see the loading
pattern. Only after trials will SMRT be able to make the right
decisions. Also it has SBST as an example that has done extremely
well with DDs.
Look at the losses of SMRT with such a small operation
(one-third of SBST) but losses three times. Why? Bendy maintenance
is definitely more expensive and not yielding as good results as
SBST DDs. Face it, my friends.
Not feasible to maintain 2 kinds of models in the long term, as
mentioned by carbikebus. However your scenario is best describing
what SMRTB should do in the next few years if they are really
serious to improve their bus operations. Gradually bring in
double deckers and pharse out the use of bendy buses and reduce
their losses in the long term.