Yes, the real crimes against proper planning were and continue to be committed in local council chambers.
For example, in the last few days, the SDCC has voted to amend their own development plan ONE WEEK after its adoption in order to allow an extension to Carrickmines and a reduction on development in Cherrywood even though the latter is to have the Luas running through it while the former is accessible only by car via the M50 and is close to significant archeology.
Development plans are supposed to be strategic. Professional planners working in local government are bound to use them for guidance but the system is broken because a bunch of councilors can change the plan at a whim (i.e. without any justification in terms of strategic planning). Someone wants to build on a flood plain? Councilors don't care as long as the next flood occurs in a couple of years time and their part in facilitating the development has been forgotten and the development levies have been collected.
Planning by definition has to be a strategic and long-term game to deliver results. Local politics is about getting your face in the next edition of the local paper. It has been an absolute disaster for the country to give those with such short term interests such powers over planning (whimsical planning exceptions for one-off-houses, arbitrary amendments to development plans, etc.).
However, every time the obvious solution is discussed (i.e. remove these powers from local councilors), there is strong and hysterical opposition often claiming it would constitute an attack on democracy or some such nonsense.
Unfortunately local councilors seemed to have deflected public irritation with the poor planning in the country by blaming professional planners, An Bord Plannala or (particularly illogically) volunteer heritage organisations like An Taisce. And the public seems to lap this stuff up. It seems a councilor has just to suggest that locals are being oppressed by one of these bogeymen (the absolute ideal being a "D4" type, An Taisce member working in An Bord Plannala) to whip people into a frenzy of indignation.
However professional planners in local government aren't completely blameless. Many planning departments have a culture which supports abdicated their duties in the face of difficult or contentious decisions. They grant permission to anything/everything, leaving it up to third parties to appeal, knowing that it'll end up with ABP anyway. This is a hugely inefficient way of doing things - adding up to a year to the process.
Unfashionably as it is to say, if it wasn't for ABP and the likes of An Taisce, the country would be in an even worse state in terms of planning.