Burning coins will increase the price proportional to the ratio of burned coins to coins in circulation. For a permanent 1% change you need to burn 210,000 BCH.
If I burn 100 coins the price in USD is unaffected, as these coins would not be part of trading market anyway.
All it means is, I hold less bitcoin.
Yes yes, the way to affect the price is to restrict the supply *on the market* while making sure demand stays consistent or rises. If restricting supply decreases demand it's futility.
