Yes, I always thought my grip contributed to the ability to Stun, or Kill the cueball more than the players using loose grips.Short answer "No."
I believe firm grip is even better than light grip, I don't care for filippino's style that much, but most of successful players are firm or even tight grip, CJ Wiley yourself used to be a firm grip if not tight as seen in the 90's videos. and it worked nicely for you.
When I was in my early 20s I bought one of those rubber roll down grips and wore it out in less than 3 weeks from my grip pressure. Hand strength is important in many player's games, I have always wondered whether that kept women from playing the speed of men......their hands aren't as strong.
Food for thought.
The Game is the Teacher