No, it doesn't. It indicates an inability to correctly express oneself. Text is perfectly capable of conveying emotion and intent; there's a whole section of the arts dedicated to it. It's been around for a while, you might have heard of it. It's called "literature". You'll perhaps also notice that there are non-native english speakers on this very forum who are quite capable of expressing themselves without causing offence or having to resort to smilies.
Saying something flat out rude, and then saying "no disrespect intended", with a fucking yellow atrocity tacked on the end screams out, to me at least (although I am a cantankerous old cunt), that every disrespect implied in the original post was, actually, intended.
If there was, actually, no offence intended, the correct approach would have been:
- Read your post before posting, think "hrm, that's a bit rude, I wouldn't like it if someone said that to me" and edit post as appropriate.
- OK, you've missed that, it's hit the interwebs. Bugger, that's rude, I didn't mean it to come across like that! There's an "edit post" button with which you can change what you've just posted (I'm not overly keen on rewriting posts, I'll usually only use that to add text, fix grammar, or remove stuff using the strikeout tag). Or copy everything and delete the post entirely, redo it from scratch. Both of these only really work if done quickly.
- Hrm, the reasonable edit window has expired, and the person has probably taken offence. The solution to this is simple - you apologise (and either take down the offending post or edit it). No smilies, no weasel words.