Simply put it together, SMRT had helped trialed the Citaro
for SBS TRANSIT in deciding to purchase the fleet.
With the period where the SMRT Citaro is on trial, SBS TRANSIT or
anybody would be able to make evaluations on the Citaro bus and
wholefully decide whether to purchase or not.
For SBS TRANSIT to decide to purchase 300 CITAROS, it must've
meant that the CITAROS had fulfilled the requirements of SBS
TRANSIT. Coupled with the drop of the euro and pound, this made it
a perfect time to acquire the CITARO buses.
I dont think its a race over who purchased the best bus. I think
it was more of seeing if the bus had fulfilled the bus companies
requirements. In this case, I think SMRT had not purchased them
because it does not meet the requirements or either waiting
till the trial period ends before making an evaluation and coming
to a decision to purchase the bus.
Whatever it is, would like to see CITAROS from both SMRT and SBS
TRANSIT for the future! 
Lol... Sounds like SBS Transit put spy to ride on SMB136C for
performance... 
