When a trader tends to pick up trading strategy he requires to be watchful. Every trading strategy has its own agenda which a trader needs to encounter before he can make decisions of trade with the exploitation of that strategy. And yes, not all brokers are providing flexibility enough to use any sort of trading strategy. Rather some brokers are imposing restrictions of scalping and other sort of short term trading approaches.
For this reason, before a foreign currency exchange trader can practice with his demo trading account and get expertise in some trading strategy he must be aware on the fact that whether his broker is ensuring him all the services which will facilitate easy execution of that strategy.