Wow, what a great site for getting info about sailboats and sailing! You guys are terrific!
I'm going with the larks head/cow hitch arrangement and if I see chafing I can, as Barry suggested, move the knot right or left a foot or two in either direction. With 40 feet of sheet on each side for my 28.5 Hunter, there's always a puddle of line at my feet even on the slack side, so there's certainly plenty of line to move the knot a foot or two.
Thanks for everyone's help.