I get nervous about exemptions for "predecisional deliberations," "to preserve the deliberative process," etc. since these usually open the door to abuses where the public agency designates documents as "preliminary" until they are not controversial. In Kansas, for example, the Garden City Telegram pursued a case against KDOT when the latter refused to release railroad crossing safety data, saying it was "preliminary." The Kansas open-records statute does not have an exemption for "preliminary" document, so the trial judge handed KDOT an embarrassing defeat and a huge bill for legal costs.
It should be noted that this occurred one KDOT Secretary and at least two KDOT Chief Counsels ago, and KDOT is now much more firmly committed to openness than it used to be.
In Pennsylvania I tend to worry more about the exemptions for infrastructure security, which are open to wide interpretation. The bureaucratic imperative for Ms. DiRienzo and her colleagues is to engage in trench warfare to secure as broad an interpretation of those exemptions as practicable, so that the amount of information PennDOT and other state agencies are required to disclose is as close as possible to what was required under the old Right to Know Law. In fact there are lawyers still doing business with Pennsylvania state government who have advised their state agency clients that the new Right to Know Law is not a "significant" change--such advice is tantamount to professional malpractice. Some OOR Final Determinations have also noted instances of agencies using standard forms designed for the old Right to Know Law when answering requests made under the new Right to Know Law.
I recently made a Right to Know Law request from PennDOT for signing contracts in District 6 (Philadelphia). I did not pursue it beyond the initial exchange with PennDOT. They found just 250 plan sheets responsive to my request, all of which were available in microfilm only, not electronic format as I had requested. They wanted $1 per sheet for prints from microfilm, and I know what PennDOT microfilm looks like, so I passed. But the response letter did note that there were sign elevations and other structural sheets which PennDOT considered to be exempt from disclosure under the infrastructure security provisions of the RTKL, and I would have had to file an appeal with the OOR in order to have a shot at getting unbowdlerized plans sets.
It took over a month from the date of the initial request to get to this point. PennDOT stores its as-builts at district level. The RTKL has a provision for a single 30-day extension at agency discretion, and it appears to be PennDOT policy to invoke this for all requests which require handling by a district. It is not possible to get a quicker answer by filing a RTKL request at district level, because RTKL requests can be accepted only at Ms. DiRienzo's office in Harrisburg. The 30-day extension would make sense if the request had to be transported in paper form by mule train to a distant satrapy, but in the Internet age (I filed my request electronically, BTW) it is a delaying tactic masquerading as workload management.
Given this experience with PennDOT and its approach to RTKL requests, it is extremely helpful to have guest-account access to the ECMS, as this very efficiently sidesteps the whole rigmarole of making a formal request.