for me, the biggest contributor to our clogged up roads are the fast influx of new cars/vehicles ( surplus or brand new )
i've witnessed a time when there was less traffic, the time when the widened roads have just been finished and the vehicles were just the same in numbers. we were smiles back then coz WOW. DAKOA SA DALAN OI

but as the years went by, here comes the super affordable KIA PRIDE. the local L300 ( PORTER ), the elf-turned to jeepney and then the SURPLUS VEHICLES .......... and BOOM !!!!! DAMN TRAFFIC JAM !!!
if the government should prohibit the incoming vehicles and focus more on another road widening, well, for Cebu we have soon our BRT ... but at least, for now, we should stop taking in new vehicles.
it's really not about discipline, coz no matter how discipline the PUJ drivers are, let's say, for a certain strip of JeepNey Stop, the one in junquera for example. there are too many 10E and 10F, even if they go by the book and disembark their passengers on the designated J.STOP, it will still be congested, coz, there's just too many of them ....