datastore retrieval

[VodkaFish]

I just upgraded from 3.6.7 to 3.7.2

I was accessing something from my datastore like this:
$parse = $vbulletin->datastore->registry->mystuff;

Then I'd use $parse to parse the post message.

After the upgrade $parse is null.

However, if I do this, all is well:
$setup = $vbulletin->datastore->do_db_fetch("'mystuff'");
$parse = $vbulletin->mystuff;

I can then use $parse properly.

I once had a problem with getting data from the datastore before, but this is different (just in case anyone recognizes this somewhat).

Was anything changed in 3.7 that would disallow my original method?

Does the way I have to do it now create any extra load on my db (this is for a decent size forum)?