software

Is there any advantage to having a little relief in your neck as opposed to making it perfectly straight?

Yes,a slightly bowed neck will help the string clear the frets.However if you have a straight neck and plan on giving it some relief,(usually about a 1/32quot; from the bottom of the string to the top of the fret),remember to reset your intonation.
To test the relief put a capo on the first fret and press the fret where the neck joins the body,(usually around 14-17 depending on the guitar).Measure the fret that is in the middle of the two points.
If you are playing with a perfectly straight neck and are getting no buzzing with good intonation and action I'd say leave a sleeping dog lay.-IMO

Yeah.

Most guitars can't handle a perfectly straight neck with low action. They aren't designed for it, they need a little relief. If you straighten the neck completely, you won't be able to achieve you best action measurement.

Only a handful of guitars (the high-end Jacksons, for instance) actually set-up well with a perfectly straight neck. I find well-build shredder-axes like straight necks, for that ultra-low quot;how-in-the-name-of-god-are-those-strings-not-fretting-outquot; setup.

The general rule is to adjust the trussrod so that when you hold down the low E at the 1st and 14th fret, there's just barely enough space to slide a thin pick between the low E and 7th fret. Once I get it to that point, I just play the guitar and make tiny tweaks so there's as little fretbuzz as possible.

I really never bother to measure since each guitar/bass will dictate its own outcome. I will sight the neck, check for relief, but I go by how it plays and responds to touch as well as if there is any fret buzz. As soon as you turn a screw somewhere on a guitar, old measurments used for a previous setup may be pretty useless.

in a word, YES, there is an advantage of having some relief ... it's easier to play

the amount of relief, like some other things, is a matter of personal taste and playing style

I kind of agree with Lew on this - I like strats and teles with a little more relief than LPs. The strats and teles benefit by having a little more sustain, whereas the LPs already have enough sustain, and benefit from better action.

I find that Fender's guidelines work fine for me - .010-.012 relief.

String Action Gauge

Instructions Measure string action at any fret by sliding the gauge from side to side behind the string. The string height markings are at increments of .010quot; (ten thousandths of an inch). When the bottom of a mark aligns with the bottom of the string, that measurement is the string height at that point.
See below for factory setup specs, low-action
setup specs, and well-known players’ setups
The charts below were compiled by Dan Erlewine, of our product development team. They’re mostly from Dan’s books, The Guitar Player Repair Guide and How To Make Your Electric Guitar Play Great (StewMac #3720 and #5199).
Factory specs show how the instruments originally shipped. They are medium-high action: reliable measurements for preventing fret buzz when you don’t know who will play the instrument or what climate it will go to.
Low-action specs are for the setup that many players prefer. They’re more difficult to achieve than factory specs, and require more adjustments depending on humidity, etc. It’s a good idea to start with a neck that’s straight, or almost straight: first adjust the neck, level the frets and dress them with a final rounded shaping and polish. Sometimes it’s even necessary to replace a nut or saddle to get the neck just right for low-action setups.
The players’ specs were all measured right at the gig, so they’re the real deal.
Measurements used in the charts below:

String height
Clearance between the bottom of the string and top of the fret 1st fret, then again higher up the neck (usually the 8th fret or 12th fret). Measured for the outermost bass and treble strings. For the players’ specs, string height was recorded at the nut rather than the first fret.
Relief
Lay a straightedge across the frets and measure the clearance at the 8th. (Or put a capo at the 1st fret and press a string down at the highest fret — the string becomes the straightedge.)
The markings themselves are .005quot; thick, so referring to the top of a mark instead of the bottom ads .005quot; to the measurement. In this way the progressive string height scale measures in .005quot; increments. from : localhost/www.stewmac.com/shop/Tools/Me...0.html#details

Thanks!

One tip I picked up from Dan Erwline's book is to make minor adjustments to the neck relief (no more than half a turn) and give it at least a day to really set in before making another adjustment.

I usually have .004quot; relief on the 7th and 8th frets on all my Pauls. I would go up to .006quot; but .007quot; or .008quot; would be too generous for me. My string height at the 12th fret is 4/64quot; Bass and 3/64quot; Treble. Remember, more relief lets you set up the action as low as possible. The straighter the neck (with relatively no relief) the more you will need a higher action. Fret buzz is impossible to eliminate. We're just going for the quot;Minimalquot; amount as we can getaway with. Fret buzz on an Electric Guitar that can not be heard thru the Amp is fine.

Fret buzz on an Electric Guitar that can not be heard thru the Amp is fine.

True 'nuff, but if you are a heavy handed player, you will get some fret wear (unless you use special alloys or stainless).

yeah, but fretbuzz ruins your tone and sustain.....