IMO KJ has over-deployment of their OC buses. Come to think of it,
why does 307 need full fleet OCs? The current quota for SMRT is
60%, there isn't a need for 100%, I feel that the extra buses can
be deployed elsewhere.
In fact if you look at the current deployment of OCs across the
7 WAB services, AM seems more capable of deploying their OCs than
KJ that just push all their OCs to their WAB services. If you
reduce the number of OCs to 60% you probably can have enough to
start another WAB service.
Actually, from my point of view, grouping similar buses together
is not a bad thing. Just that in this case KJDEP decided to group
OC into 307.
Having similar vehicles together can help maintain frequency,
coz different vehicles take different time for boarding and
alighting. Just for e.g, hispano o405 rigids probably uses the
least time for passengers to board and alight, as theres no bus
stop lock fitted (the bus can move off while the driver closes the
door at the same time), OCs cant do this due to the safety feature.
If the two types are mixed together, it may also be a factor why
buses bunch together.