No? He coaches defense. He needs elite defensive players at every position group to be successful.

A team can score points and still have a great defense, but it helps when the defense isn't constantly on the field like A&M's has been. All defenses play best when they can get off the field and give the ball back to an effective offense. Football isn't played in a vacuum though and there's so many aspects to examine.

When a defense can't get off the field it gets gassed. Gassed defenses = bad defense. Examples of gassed defenses:

LSU vs Auburn 2014
Texas A&M vs Alabama 2014
LSU vs Mississippi State 2014
Clemson vs West Virginia 2011/12
etc, etc

Defenses also rely on being fundamentally sound and limiting 3rd down conversions. The biggest stats in defense are turnovers, 3rd down success, and scoring. If you are good in those three categories, you'll have good defense.

2014 LSU:

20 turnovers gained
36% on 3rd down
17.5 points/game

2014 A&M:

13 turnovers gained
40.78% on 3rd down
28.1 points/game

2011 LSU (Chavis' best defense):

30 turnovers gained
33.97% on 3rd down
11.3 points/game

2013 LSU (Chavis' worst defense):

19 turnovers gained
38.30% on 3rd down
22 points/game

2012 A&M (A&M's best defence in SEC):

16 turnovers gained
32.20% on 3rd down
21.8 points/game

Snyder had a better defense in 2012 than Chavis did in 2013. His 2012 unit was also better on 3rd down than LSU's unit in 2011.

For funsies:

2009 Clemson:
30 turnovers gained
38.74% on 3rd down
20.4 points/game

2010 Clemson:
20 turnovers gained
38.54% on 3rd down
18.8 points/game

2011 Clemson:
23 turnovers gained
40.95% on 3rd down
29.3 points/game

22.83 points per game is Kevin Steele's average over 3 years which is similar to LSU's 2013 defense. Kevin Steele's defenses average more turnovers gained though.

2011 Alabama:
20 turnovers gained
24.46% on 3rd down
8.2 points/game

2014 Clemson:
24 turnovers gained
27.41 % on 3rd down
16.7 points/game

Draw your own conclusions from the stats provided. Keep in mind that there are better positional coaches at LSU now (2015) than at both Clemson from 2009-2011 and at A&M from 2012-2014. LSU's secondary coaches have been elite from 2009-onward. LSU's defensive line coach has been a liability from 2009-2014.