what? wat about the advance french (1.e4 e6 2.d4 d5 3.e5) and KID (1.d4 Nf6 2.c4 g6 3.Nc3 Bg7 4.e4 d6 5.Nf3 0-0 6.Be2 e5 7.0-0 Nc6 8.d5 Ne7)
a strong opening

It's definitely correct to say that you shouldn't overextend your pawns but as Bdsr has mentioned many respectable openings have this since it isn't an overextension but a good move to limit the opponent.
my comment was pretty bad, i narrowed it down like a doofus, after all capitilizing on a opponents weakness to reduce thier ability to advance is a godsend strategy.
it may have dawned on me late, but i have realized one thing any player must do to ensure a strong opening, never advance past the third and 4th ranks unless you get a rare chance to attack the f6 knight with a e4 pawn. then secure a stake in the center with a follow up of d4. anyways the reason why is because this is whites weak files, while the same i for black being the 5th and 6th