I remember the first time I found Lugia. I didn't know what I'd found so naturally I didn't save. Saw what it was and thought "Hey, Lugia! I'm gonna try to catch it!" Suffice to say my level 100 Feraligatr didn't like that plan. I never really understood how to play Pokemon, I only ever trained one Pokemon and I taught it whatever HMs it could learn. I believe that particular Feraligatr knew Cut, Surf, Strength, and Whirlpool. 1 attack and that Lugia was forever lost.
I also remember once I tried going through with a Pidgey. As I said, I didn't really understand the concept of "train more than one Pokemon," so all I had was that Pidgey. I got to Jasmine without any problems, though.