User blog comment:B214/Chapter 383 Surfing Lucy thoughts and analysis/@comment-197.226.178.50-20140509121045/@comment-7418318-20140512063040

No.

Counterexamples: Lucy and Juvia vs. Vidaldus, Lucy vs. Hughes in Edolas.

The reason why Lucy considered Aquarius her most powerful Spirit was, because she was at the time. And she's been so long that Lucy kept calling her that for a little while longer.

When Lucy first thought of Aquarius as her strongest Spirit and then realized that she also had Loke now during the fight with Angel, that was the last time she thought of Aquarius as the strongest of her Spirits.