I'm just going to ignore chuee or whatever his name is since he's rather childish.
Just like Lucas, Zelda isn't viable on her own, so I go solo Zelda only in specific MU's and so do many others. I could name you about 5 solo Zelda's and maybe 15-20 Zelda players that are more proficient with Sheik(such as myself). Point is Ganondorf is played more than your character so calling out someone's character like that is rather pointless considering your character is BOTTOM 5 in the game for tourny attendance/placings

.
Marth doesn't **** Sheik....Neo think's it's 45-55 Marth adv.
Squirtle is also a terrible MU for Lucas and I would imagine there to be others. Zelda and Lucas both suck so I see no reason to bring up there matchups when we are talking specifically about their MU with each other.
Also, Sheik is in a whole other league then Lucas.....bordering on viable.
Lastly, Lucas' nair has little range and would by beaten by the majority of Sheiks' moveset so if by chance I shielded the first attempt and was shield poked.....it would be player error on my part to have the same thing happen repeatedly.