Texting is dancing. You text, must wait for other person to reply. May take a day or so depending on how busy they are/how attached they are to their phone. A conversation on the phone that takes 5 minutes may spread out to 5 days via text. MOST of what we say isn't in the words themselves but in how we say it so texting is vulnerable to much misinterpretation.

Just my $0.02. Maybe SM means something different.