Spot-on, Andreas.
Compared to Black Powder's neutral fouling, the phoney's are bad news as they don't need moisture to hurt the gun, whereas BP fouling does.

The actual effects on the steel are also different - whereas BP fouling, with the addition of moisture (above 35% humidity required), will cause a barrel to rust and eventually pit, the chlorates actually eat away (corrode) the steel, beneath the surface causing a little bubble, then the 'blister' comes off, leaving sharp edged pits with a V shaped bottom. These will deepen from normal firing pulses & have been known to go through 1/4" of steel in short time.

Yes, I know, some guys have been using this stuff for years and have not hurt their barrels - they think. A bore scope will show whether there is damage or not. Some of it depends on the barrel steel's compostion, ie: alloys. Most people who use this stuff don't shoot much and perhaps that's a saving grace. I've seen too many barrels ruined by it in as little as 6 months.

For me, antique's need real black powder. It is user friendly, but, of course, must be cleaned properly - cold water works wonders and is recommended by H&H for their original guns, shot and rifle. Then dry, use a water displacing oil like WD40, then preserving oil if your ambient humidity is fairly high.