Yes, it is important to allocate dedicated time for practicing answer-writing and improving analytical and argumentative skills within your study plan. Here's why:

1. Enhances critical thinking:
- Regular practice of answer-writing helps in honing your critical thinking abilities.
- It enables you to analyze questions, identify key points, and develop a logical and structured approach to answering them.

2. Improves time management skills:
- Answer-writing practice allows you to become more efficient in managing your time during exams.
- By dedicating specific time for answer-writing, you can learn to allocate appropriate time to different sections, ensuring that you complete the paper within the given time frame.

3. Boosts confidence:
- Through regular practice, you gain confidence in expressing your thoughts and opinions effectively.
- This confidence translates into better performance during exams and helps you tackle challenging questions with ease.

4. Develops clarity and coherence:
- Answer-writing practice helps you improve your ability to present ideas in a clear and coherent manner.
- You learn to structure your answers, provide relevant examples, and support your arguments with evidence, making your responses more convincing.

5. Enhances communication skills:
- Practicing answer-writing not only helps in exam preparation but also improves your overall communication skills.
- It enables you to articulate your ideas concisely and effectively, making you a better communicator in various professional and personal settings.

6. Provides feedback and self-evaluation:
- Dedicated time for answer-writing allows you to evaluate your performance and identify areas for improvement.
- You can seek feedback from mentors or peers, enabling you to rectify mistakes, clarify doubts, and refine your approach.

7. Builds exam temperament:
- Regular practice of answer-writing helps in building the necessary temperament required during exams.
- It reduces exam anxiety, improves focus, and enhances your ability to think and respond under pressure.

8. Increases familiarity with exam pattern:
- Allocating specific time for answer-writing familiarizes you with the exam pattern, types of questions, and word limits.
- This familiarity improves your understanding of how to approach different types of questions and maximize your score.

Conclusion:
- Allocating dedicated time for practicing answer-writing and improving analytical and argumentative skills within your study plan is crucial for UPSC preparation.
- It enhances critical thinking, time management, confidence, clarity, communication, self-evaluation, exam temperament, and familiarity with the exam pattern.
- Regular practice in these areas will significantly contribute to your overall performance in the UPSC examination.