Update on Issue
Okay, I think I have figured out what the problem is and it deals with the way the URL reacts based on your default number of posts per page. Basically, if the result from the search points to a post in the first page of the resulting thread (based on your default number of posts per page) then the highlight will show up, if it is on page 2+ it does not. You can't really tell from examining the link in the search results as it points to a specific post number, but when you choose the link, it changes the URL based on your settings and if it lands on anything not page 1, (in other words no page number) then the order for "highlight" disappears from the line.
Here is an example: Searching for "splinter" in all forums, you get a lot of results, but if you scroll down just a bit to 3/5/2009 you will see a topic title
Tk-730 with 1 reply (so far), if you click on the link
Tk-730 ( <== you can use this one instead) you will be taken there with the hightlight. The next search result just below that is from a topic called
6.25 channels that has 25 replies (as of now). If you click on the link that reads
Look at 90.35, note (30) for our frequencies,... you will be taken to the proper post, but the word is not highlighted.
Both of the search result URLs are constructed the same, the only difference is where you are going based on your posts per page setting (the forum default is 20), see below:
Code:
Result URL from 1st example above:
http://www.radioreference.com/forums/kenwood-forum/137371-tk-730-a.html?highlight=splinter#post1020592
Result URL from 2nd example above:
http://www.radioreference.com/forums/railroad-railfan-monitoring-forum/134720-6-25-channels-post1020165.html?highlight=splinter#post1020165
In any case, it is a minor bug and I will report it to Lindsay via our bug reporting software, thanks for finding it.