Please, for the sake of your teammates, be quiet.

More often than not, your teammate isn't dying on purpose.

You're not being helpful by pointing out obvious strategies.

Nothing is more tilting than getting told to, "Stop fighting, stay under your turret," when you've been under your turret, missing experience and farm, getting poked for the past 3 minutes by a ranged, manaless champion with wave clear and sustain.

So please, keep the "helpful" comments to yourself. Typing is distraction as is, unless you're typing something a ping can't communicate, that puts your team in a better position, there's probably something you could be doing. Even if you're just walking back to lane, instead of typing, pan the map. See where everybody is, you might be able to get a number's advantage.