Hi Reds he means play with a looser grip in particular your bottom hand as this will absorb the impact Of the ball what he is stating is that by having hard hands you are more likely to get caught by close fielders with softer hands the ball wont come off the blade with as much velocity this will also allow you to steer the ball across the ground and into the gaps
I've been thinking about this subject recently and one of the conclusions I've come to, I may well be incorrect, is this.
I'm predominantly left handed, though I'm proficient at certain things with my right hand, I wouldn't say I'm ambidextrous, but I bat right handed and play golf also right handed, because of this my stronger left hand, the hand I've been told to grip the bat hard with, naturally helps me get over and keep the ball down and I'm barely gripping with my right hand, two fingers and the thumb, a big advantage I would've thought compared to a right handed person batting right handed who is understandably going to grip harder than they would like with their bottom hand leading to the toe overtaking on impact or playing more cross batted shots.
Unfortunately the opposite applies to my golf swing where my left hand wants to do all the work leading to me breaking my wrists too early and getting the club head in a poor position which needs to be corrected at some point in the swing before impact.
In my experience playing golf, if you have one flaw in you're back swing it needs to be corrected somewhere in the downswing to make a decent strike, two wrongs making a right, there are plenty of examples of this in professional golf, Jim Furyk, Bubba Watson etc etc the list goes on, in fact there are few technically correct golf swings even at the elite level.
Drifted off my point a bit towards the end but I hope this makes sense.