I don't think it can be a bad idea. It looks like it has worked for Rose, Mahan and of course Tiger. These 3 have all been playing well under tutelage of Sean so Lee is probably making a good move.
It can't hurt because his game seems to have taken a step back of late and at 40 he needs to turn it around sooner than later. I'm not sure if it will show positive results this week as it takes time but you never know. Sometimes with a ball striker like Lee it just takes a little confidence building!!