Having taken the NCEES PLS exam several times with unsatisfactory results I'm convinced the more one takes it the less chance they have in passing.
Think positively. Study the Manual of Surveying Instructions (1973 & 2009 versions) on sectionalized lands, Boundary Control & Legal Principles (Brown, Robillard & Wilson) and the Land Titles & Burnt Records Act. You should do well as long as you remember to single or double proportion as a last resort. Good Luck!
I would agree, stay positive. I would also question your experience you are gaining since the FS. If you truly are getting the well rounded experience and working on both the field and office nearly all the (correct) answers will come to you naturally based on your daily experiences without studying.
You are entirely correct about the fail rate increasing for people who have taken the exam multiple times. I've heard the statistics on this a number of times over the years sitting in on the public meetings of the Mass. board of registration. The same holds true for the engineering exam. The Mass. board will only allow a person to fail the PE or PS exam twice, and will then require the person to take some classes and/or document more experience before allowing one to sit the exam a third time.
The most common reason for multiple failures of any of the exams is that the examinee does not significantly change what they do to prepare on subsequent attempts. Getting in regular study time is incredibly important, but the answer isn't always allocating more time. More likely it will be either what you are studying and/or how you are studying it.
If you have a tendency to spend most of your time on 2 or 3 aspects of surveying at the expense of others commonly covered on the exam, reverse your time allocations per subject. Many years back, I was working in a state that authorized surveyors to design gravity flow utility systems (storm and sanitary sewer). A coworker had just failed the exam for the 2nd or 3rd time, and it turned out that one of his weakest areas was the hydraulics & hydrology of gravity system design. He was complaining that if it weren't for those questions, he would have passed. Allowing him to continue to vent, I learned that he knew going in on that latest attempt that this was his weakest area, so I asked him what he did to build his knowledge in it between exams.
Nothing. He didn't study it at all because in his opinion, it had nothing to do with surveying and shouldn't be on the exam. I suggested that since the state's definition of surveying included it, it will almost certainly be on future exams, so it would be a good idea to fill in his knowledge gap in that area. I offered to let him borrow my text books on the subject. He refused the offer, more adamantly asserting that pipe design had nothing to do with surveying.
I wonder how many more failures it took for him to change his attitude on that?
Point being, many tend to study what they're already fairly comfortable with and end up going into the exam well beyond minimum competence in one or two areas covered by less than half the exam, but being slightly or way below minimum competence in the other areas covered. Study the areas you are not comfortable in with the majority of your study time and provide just enough time to your strong areas to ensure that you don't lose your edge in them.
A regular part of your study plan needs to be in the form of working test questions under similar conditions as you will encounter during the exam. Whether you do that by allocating 15 to 30 minutes of each study session to exam problem solving, a 1 - 2 hour session each week, or a 2 - 4 hour session each month should depend upon how often you need to measure what you're learning in order to adjust your study content & methods.
Use test questions for which you also have an answer key. Test yourself as you begin your study routine for the next exam and then grade it, or have a knowledgeable LS grade it for you to learn where your strong areas are and where your weak areas are. Develop the rest of your study plan based on those results and check your progress regularly under exam-like conditions.
Or, do what you've done in the past and get similar results to what that routine has gotten you.
Study well, do well.