nanci:
Interesting question. Yes, it does get a lot more crowded in "season." But, it's really rather relative, I think.
If 25 cars in line at the light at Morse & CR466 is a traffic jam, then it's quite possible that you'll see a traffic jam there.

[I counted that many one weekday morning last February!]
Parking, quite frankly, seems to me to be always a problem, even in the summer! I continue to be amazed that handicapped places are few and far between, and the ones closest to wherever one wants to go are inevitably taken - I hope by folks who need such! [I no longer do]
And, yes, it is very hard to get in to restaurants in the winter. Since virtually no one takes reservations (except maybe for a really large party), it's what's called a crap-shoot!
On the other hand, my brother and his family and I (they live nearby but not in TV) have decided that we can put up with eating late in the winter, and so frequently don't even arrive at a restaurant until 7:30 or even 8:00. Our wait time may be as little as 5 minutes!
We've also learned that parties of 6 often can get a table sooner than a twosome! Not everywhere, I suppose, but that trick almost always works for us at Cane Garden CC!
I heard not too long ago that 70%-75% of Villagers are full-time, so maybe the snowbirds and visitors are taking a page out of our book: stay forever!
I don't think you should worry about the traffic and the crowds. Everything is such fun and folks are (99.99%) so friendly. And, we all put up with the minor inconveniences, now and then!
Steve