mcrider/pkp-lib — comment on commit 97f714707517e53c755e81f78e578e6589f5b730
File: classes/user/PKPUser.inc.php line 381
By mcrider:

There is a bit of a performance benefit to caching here, since we get the user interests in JSON and as a formatted string on the same page. If we can do all the DB queries on the fetch where we get the data for JSON, we can reuse the results for when we need the interests as a formatted string (to display in the javascript-disabled textfield). The alternative is to have one function that returns all the interests formatted both ways (json string and comma-separated string) returned in a single array. But it looks a little nicer to me this way IMHO.