The name of God & Goddess (Mantra) and God and Goddess are the Same, they are the mind tools that dial the telephone # of the name you are repeating. When you do mantra you are calling that person, you either believe in the traditions you are boring from or do not even bother teaching these traditions.
Shiva is real or you are just playing a game. If you practice Yoga one follows Shiva because Shiva is the 'Lord of Yoga and Tantra' the purpose of Yoga to know Shiva and Shakti, who do you think Ishvara in Yoga, Tantra, or any of the auxiliary subjects of India is including Jyotish? Where did Yoga come from it came from Shiva. Why even bother with any of these subjects if you do not even believe Shiva and Shakti are real? Let alone teaching these subjects without a full understanding, it would be like teaching Christianity without believing there is a Jesus Christ or God in the Christian faith. Shiva is God, Krishna is God, Brahma is God Tri (Three) Durga, Laxshmi, Saraswati are the Goddess's and they have many names, many telephone numbers to call this is called Mantra. Om lets you into the circle of all 3 and beyond. It is both you can not have mastery without Dual and Non Dual they both exist.
You must Master Humanity first!
One can be impersonal or personal about this but it all leads to the same place. If you practice Mantra, she is going to come to you, you may start out as impersonal but eventually she will show up and then what, you better know what you want, and where you want to go. If you want to park in neutral go ahead but it is much better to play in the Divine Game of Love and for Love you need two and exchange between two. Whether that be God/ Goddess and you or your beloved.
Or you can choose 'Mastery' and be both Personal (Dual) and Impersonal (Non dual), Mastery is Multi tasking. As Above so Below, this is the Ultimate Tantric Mastery. You can be both and that is Baul both Dual and Non dual. Advaita and Dvaita. The path of the Avadhuta. Why throw the baby out with the bath water?
Trishula Das
http://vedicgoddess.weebly.com/goddess-vidya-blog
Art: Shri Lalita Tripurasundari
by Rajeshwar Nyalapalli, Andhra Pradesh