Fundaments are important and fundaments dictate that LTC was planned to be mined by CPU not by GPU, this is the worst error made by LTC developers, Period. 
It was designed to resist HW scaling - which it does - very well.
Anybody with just an inkling of how computers work understand that's it's virtually impossible to design an algo that cannot be scaled.
Im not talking about technical issues, Im talking about the economical fundaments based on CPU mining VS GPU mining and the impact on the coin in the market caused by this switch; LTC was designed to be mined by CPU in his fundaments.
if I remember btc was designed for cpu too
but then artforz I believe was the first to gpu mine on it