Do you mean how many people can be in it when parked and set up for camping? The CCC is the maximum weight you can add to the trailer, either by modifications, options and upgrades or by clothing, food, gear, sewer hoses, chocks, etc., etc. that get added onto the dry weight.
You don't have to worry about the weight of people and other things inside the TT when set up. Don't forget that you'll have stabilizer jacks taking up weight on the frame. If you find you have excessive bounce, you can use a bottle jack under the frame just ahead of the front axle. BTW, have now found out that electric stabilizer jacks just aren't all that stable and you'll still get annoying rocking, rolling and bouncing but there are more things you can do stiffen things up.
But... The cargo carrying capacity is often way inflated. In our case, we have only 200 lbs of CCC left after being loaded up for camping. We can't travel with even one full tank of water without going over the GVWR of the trailer.
The only way to get an accurate actual cargo carrying capacity for a trailer is to take it to a scale and weigh it. The factory dry weight does not include factory options, dealer installed items (propane tanks, batteries, etc.) or anything the owner adds. Some things you would expect to be included in the dry weight aren't like the microwave. Depending on the TT size, you will typically be 1,000 - 1,500 lbs or maybe more, over the factory dry weight.
That particular TT of 34'-3" long has a dry wt. of 5980, dry tongue wt. of 680 lbs and GVWR of 7600 lbs. As you say, the factory CCC is 1620 lbs. For a trailer that long, by the time there is another 1000 - 1500 lbs added to the dry weight, that can leave you with very little actual cargo carrying capacity left. You *could* possibly find yourself with a problem.
Coachmen is a Forest River brand. I would go over to the FR forum and see what you can find out about actual weights for this unit. That's a very good forum for info.
Now, when it comes to a tow vehicle, the payload capacity is a whole other story.... That's when you really need to figure out and pay attention to the weight of passengers, pets, groceries, firewood and other things you may put in the back of the truck. Then you need to add the TT tongue weight onto that. I'm gonna guess that the tongue wt. on that Coachmen is around 1,000 lbs (but could be higher). The weight of passengers and all the rest of your stuff canl add at least 400 - 500 lbs. So that's easily 1500 lbs of payload capacity your truck has to have. That's a stretch for a lot of 1/2 tons. As in a TT, the only way to get an accurate payload capacity on a truck is to go to a scale and weigh it and subtract that from the GVWR on the door jamb sticker. Despite what some may tell you, the payload figure on the door jamb is often well above the actual amount. Factory options, dealer installed accessories and owner installed items are not included in it and besides, it only includes for a 145 lb driver and full tank of gas. You may also need to look at the GCWR (total TT wt. + TV wt.). If it were me, I'd be looking at a 3/4 ton truck for this length and wt. of a trailer, but you're going to get some that say some 1/2 tons are perfectly fine.
Unless you don't care about overloading your tow vehicle, it's a very good idea to know what all of your actual weights are on the tow vehicle and trailer. IMO, it's best to stay within weight limits and capacities for safety reasons, plus it can reduce wear and tear on the TV.
On the WDH, I would caution against buying one until you know for sure what the actual tongue weight is. The spring bars come in different ratings and you don't want to end up with a set that is under or over-sized because it can cause some real problems.
Hope this helps. Probably rambled on too much...
Gil & Deb & Dougal the Springer Spaniel
2014 KZ Spree 262RKS & Ford F250 supercab V10 4x4 LB