Is performing the bleeding procedure really necessary for the cooling system????

[blau]

O.K. I drain and fill the (so call life time) cooling fluid. I done this many times on various cars for years. What I always did was just fill up the radiator as much as I can and drive it around the block let it cool down and add some more fluid and then drive it for a few miles and add some more fluid and I am done. I find with this method the cars never even comes close to over heating and I add less than 1/2 gallon of fluid (I figure 1/2 gallon short will not harm the car). And then I find that I don't have to add any more fluid for months if not years.

But recently I learn that there are procedures to bleed the coolant system and some cars even have bleeding screws.

So my questions is? Has what I been doing for years sufficient? I think it is. My reasoning is if there is air in the system the air would rise to the top which is the radiator cap.

What do you folks think???