hah! yes. The lisp effect is very noticable but the main thing for me is that not all "th" in English are the same. The (icelandic) Þ only accounts for a portion of them. Others are more similar to the Icelandic letter Ð (ð, eth). For example "The" would probably be closer to Ðe than Þe. So when I was reading your posts I was reading them with the "harsh" Þ which made words like "The" sound quite weird.
Examples of Þ and Ð words in English based on my limited english knowledge and my non native dialect. Icelandic words in paranthesis for fun and for showcasing the similarities between the two languages:
- Thin = Þin (Þunn)
- Thick = Þick (Þykk)
- Thief = Þief (Þjófur)
- Tether = Teðer (Tjóðra)
- The = Ðe (N/A)
- That = Ðat (Þetta)
- This = Ðis (Þetta)
- There = Ðere (Þarna)
...etc
PS: Oddly enough, there is a rule in Icelandic that says no word can start with the letter Ð. So seeing "Ðe" feels weird grammatically. But it does not make it in anyway less pronouncable.