Tsuyoshi wrote the lyrics for some of the songs. Maybe that will give us a glimpse into his true feelings?
Yes. Tsuyoshi and Koichi reflect their feeling of the time through the lyrics they have written. That was what they said, so please pay attention of what they wrote XD However, Koichi has admitted that he doesn’t like exposing his feelings through his lyrics and he is not as good as Tsuyoshi with words, so Koichi rarely wrote the lyrics for his solo songs although he was the one composing all of the melody. On the other hand, Tsuyoshi loves playing around with words and particularly good at them. Hence, he wrote the lyrics, as well as composed the melody for all of his solo songs. Tsuyoshi’s lyrics are usually very poetic like his J-web entries, pretty hard to interpret and equipped with hidden meanings behind them.