... that SMS speek is intended for point-to-point communication - one sender, one recipient. The sender makes writing the message slightly easier, but understanding it slightly more difficult, but this is acceptable as it only needs to be received once.

However - in an internet forum, there are many recipients of the message, and the sender burdens each of the recipients with deciphering the message. Combine that with the fact that here, the sender mostly asks the recipients for free help, many recipients will not feel like helping someone who would not just want them to work on solving the problem, but also work on deciphering the message.