Mako's right. Escort doesn't necessarily mean one has to stick by the buffs all the time. Historically, this sort of close range escort proved to be less effective than free-range pre-bombing sweeps by fighters.
When escorting, stay high above the buffs, fly about 5~10 minutes ahead of their flight path and sweep. You don't have to necessarily shoot anything down. Just keep the enemy planes low. I have seen many "escorts" fail, because they are too eager for getiing kills.
Just keep them low. When after reaching target destination, stay above the field and keep swatting the people trying to crawl up. Keep them low. If there are enough numbers(like 8~10 escorts), send about 1/3rd of the escorts to the nearest field of the target destination and CAP there.