A couple more notes after riding today:
1) This week will be extra busy. When we got in line for Islands of Adventure at 8:20AM this morning, they were handing out registration cards that they said we had to use to enter the Wizarding World of Harry Potter between 9:10 - 10:10AM. We could stay inside after 10:10 but they were staggering entry into Hogsmeade to keep the crowds under control. When we did get to the castle at 9:15, the wait for Forbidden Journey was already 60 minutes! Lines for all the shops and the Three Broomsticks were also really long at 9:15 AM. if you are staying at one of the resorts at Universal, you can get into the park before 9 and I think be able to ride Forbidden Journey before 9 as well.
2) I wore loose pants today and the fit in the modified seats was much better. I could even get the third click on my own. I think my tighter jeans were creating bulges and barriers on Saturday, so if you think you migt, have trouble, loose clothes might help.
3) The single rider line is a good deal for saving time - from what we could tell, the wait is almost nothing. You do miss a little bit of the castle and you do get separated from your group when you actually ride, but once you're in the seat, you feel like you're on your own anyway, so it doesnt make much difference. Once you are in the single rider line, be careful you don't get back into the general line around the lockers - that is easy to do! Also, when you are a single rider, you will probably ride in the far-right seat on your bench, which feels like a wilder ride than the far-left seat. I thought it was better, but it was too much for my husband, who did feel sick afterwards even though he was fine riding in a middle seat the two previous times.
4) As a side note, the seats in the IMAX theater in the City Walk at Universal are really roomy. I usually hate crowded movie theaters with everyone jammed into the seats, but the seats were very comfy and so big that I didnt even need to use the armrest I shared with the person next to me.