The TV does a good job of distracting the majority of your attention and in particular your creativity (the can is probably a better option for the latter) to the point where you’re just aimlessly running up and down the fretboard playing stuff you already know. If you’re playing mindlessly then what’s going to come out of your guitar is the stuff that you can play without thinking. This is all well and good if your goal, or the lack thereof, is to hone your already honed skills, just don’t be surprised at the absence of any noticeable improvement in your playing.
What Did I Just Play?
The guitar is a sense-oriented instrument and if one or more of those senses is temporarily occupied, it’s not being worked out and is almost not participating in the practice session. Many guitarists claim that they practice scales while watching TV, but to practice scales effectively you need to pay attention to what you’re doing. If your fretting hand needs work you need to pay attention to that, if your picking technique needs an overhaul then you’ll want to focus your attention on your picking hand. If your timing is off you’ll want to focus on that, and so on. Aside from the technical benefits of learning/practicing scales, your ear needs to be at the heart of things to really be able to internalize those scales. If your ear is absorbed in the TV then practicing scales becomes a largely redundant and purely mechanical exercise.
It depends what you’re watching on TV but most programs are beyond mindless, besides, if you’re practicing guitar you don’t actually want to watch anything that interesting otherwise you’d stop playing guitar and just watch TV. When you’ve found the perfect channel with content that’s interesting enough not to either turn the TV off or put the guitar down, you’re all set. The only problem is inspiration; I find my playing starts to become as dull as the program I’m half-watching.
States of Mind
People watch TV to switch off for a while, to quieten down that internal monologue, which is no bad thing if it puts you in a relaxed state. While I wouldn’t go as far as to say that TV can take you to an almost meditative and highly-receptive state, it must be somewhere along the spectrum.
Glued to the Guitar
It’s no bad thing either to always have a guitar round your neck. Many great players have mentioned this in interviews, including Jeff Beck. The sheer amount of time you spend attached to the guitar must have some effect on how well you can play it, or at least be a contributing factor to familiarity with the instrument, or muscle memory.
I imagine that watching TV while practicing could come in handy if you’re practicing something incredibly tedious like a sequence of arpeggios or some Yngwie Malmsteen lick that you’ve half gotten down. Under normal circumstances you’d give up after about five minutes as the sheer tediousness of it would send you over the edge, but with the TV on time will just fly by and before you know it you’ll be on repetition number 1000, and well on your way to mechanical mastery.
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