Gas Insert - Replace Tempered Glass with Ceramic Glass?

My home has a cheap B-Vent Gas Insert that doesn't put out much heat.  B-vents aren't as good as direct vent gas inserts.  I am buying a wood burning stove (Green Mountain 60) because I'm sick of paying the gas company for my inefficient furnace that is constantly goings, and I live in a pine forest.

When I had the installer come look at where we want the stove, I also had him give me some ideas regarding this gas b-vent unit I have.  I wanted to see if I could put the stove there, but because my chimney is only rated for a B-vent it would have cost a fortune to replace the chimney for anything else.  So the gas b-vent unit will stay there and a wood stove just around the corner.

The installer did give me some advice about how to get more heat from the b-vent when we want to use it.  By replacing the tempered glass with ceramic glass he says it will put out a ton more heat.  He also said this could potentially overrate the appliance's safety rating because b-vents aren't designed for higher thresholds.  Indeed I did find this when researching ceramic glass replacements, " A general rule for the glass you need for your fireplace is that if you have a prefab fireplace, you cannot place the ceramic glass on the fireplace! "  link

He made it sound like it's not something the manufacturer would want to be done, but that it probably won't cause any issues.  I do trust him and he seems to be an expert on the subject.  But before I burn my house down I thought I'd ask what you all think.  

Are you sure it isn't ceramic glass now?  Regardless I really don't see it making that much difference honestly.

It's puzzling to me as well. The burner will put out the exact same number of BTUs/kJs regardless of the glass.

I'm guessing that the tempered glass is thinner and less dense than ceramic glass. So perhaps the ceramic essentially acts as a thermal mass, heating up more slowly and radiating heat longer? But perhaps that would also heat up the rest of the internal components, and they are not designed or rated for that?  

Anyway, I don't see how you can get a lot more heat output without redesigning a lot more than the slab of glass in front. My 2c.

Thank you fo your replies.  I've been digging into this myself.  I asked a few glass manufacturers and they both said this isn't true unless he were to either increase the gas output of the fireplace or bring the fire closer to the glass (which would not be possible with my current tempered glass because it can't sustain the heat).

I need to circle back with this person and double check if he knew this.  It's possible he is wrong, or maybe he was talking about turning up the gas.  Either way I wouldn't go this route because my intention is not to burn more gas.

I can't imagine he's right about this without changing something else.  thanks