Not a stupid question at all, Kay.  Yes, it does get somewhat more detailed and you have to go back much farther in time (generally 150 years) in order to pick up the severances of coal, oil & gas and other minerals.  You also need to be familiar with the way in which the laws of the state in which you are searching deal with sub-surface interests.

For example, there was a case here in PA in the late 1950s which ruled that natural gas is considered a part of the general title to the land, separate and apart from the rest of the mineral estate.  Because of this, severance language in Pennsylvania deeds must specifically mention natural gas.  It gets even more complicated when considering coal rights, due to recent rulings that owners of coal rights also own the rights to a gas called coal bed methane.

Working here in Clearfield County, PA has proven to be challenging because of unrecorded deeds and legal descriptions which are defective or in some cases non-existant.  I've been told by some of the local attorneys that landowners around these parts were very private, almost secretive and for some reason didn't want their neighbors to know exactly what acreage they owned.  Heirships can also be a challenge, and many of the older deeds were handwritten by clerks whose penmanship left much to be desired.  When I'm trying to decipher some of these old conveyances, I sometimes wonder if the author scrivener simply said, "Heck with this...in a hundred years, who's gonna care?"

All other things being equal, a title is a title is a title, I suppose, but if you're going to make the switch, you might want to look into some of the courses offered by the AAPL (American Association of Professional Landmen).

Hope I didn't scare you too much, just some things to consider.  Good luck to you.

Regards,
Scott Perry