Quote of the month:
"It's easy to see golf not as a game at all but as some whey-faced, nineteenth-century Presbyterian minister's fever dream of exorcism achieved through ritual and self-mortification." ~Bruce McCall
As for teeing it up, what Ian said - about 1/4 inch. As for distance, you should get a bit more distance off the tee than off the deck. The reason for this is 1, less resistance from the tee compared to the ground and 2, the ball is a slight bit higher, which will slightly flatten your swing, giving you a bit more distance as well. We are not talking huge a diffenence, but maybe 5 to 10 yards max depending on the club.
Every time you get a chance to use a tee, do it (unless it's a short par 3 and you're looking for backspin).
For irons, you only need to tee the ball high enough to create the best possible lie - like others have said, 1/4" is a fantastic guideline.
On my local course, there's only 3 holes where a fairway wood is appropriate for the tee - everything else is irons. I tee 'em up to the top of the grass in the tee box, and let 'er rip.
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