If I paraphrased the passage, it would read: maximum productivity is achieved when there is a clear time frame and is no more than 30 minutes long.

While my paraphrase includes the content of the passage, it misses the "argument", being that maximum productivity meetings NEED to have a clear time frame and be no longer than 30 minutes.

To address find-the-conclusion questions moving forward, it is important to include the standpoint of the passage as well as identify the presence of any necessary conditions

When you are receiving your PT scores, are you reviewing the incorrect questions? Also, if you have been consistently studying for the LSAT, you may be burning yourself out. I would reduce the time studying (like from 4 hours to 2 hours) for a week to allow yourself some space for revaluation. Focus on the drills, but more importantly, see if you are able to explain, aloud, your reasoning for picking an answer to a friend (or a rubber duck).