Well he was the replacement for Murray Walker, the king of jibberish (in a nice way off course) and thats one hard act to follow. I heard on the coverage of GP2 that it was like having a load of bricks placed on the side of your head. There must be a better analogy for describing G forces, even for the layman that sounds like something from the playground. F1 fans are an intelligent bunch of people (mostly) and even for the new fans this must sound like nonsense.
My home made G tester
* The weight of one's head and helmet is added for every 1G gained in a lateral direction of force, i believe !!
* lay on the floor on your side with your head off the floor and horizontal = 1G. (sat upright =0 lateral G)
Try that for 1hr 30mins and your neck will get tired, factor in turn 8 (4+Gs) and the average corner at 2-3G's
Result = very sore neck and unable to move for the rest of the week (the results are speculative and dependant on your level of fitness and strength of neck/shoulder/back muscles. I have not carried out the test myself but if you choose to don't try placing bricks/dogs on the side of your head as this could be distressing for both yourself and the family pooch)
I'm not sure how much the average lab weighs let alone the average human head, so in turn his explanation of G is unlikely to help anyone. 