Making transaction calls act like a Java method call would

After trying to replace my Java method calls with the equivalent
Prevayler transaction calls, some things no longer worked. In Java,
when I passed in an object and manipulated its contents, it would come
out as changed on the other side. That's because the copied reference
inside the Java method is still pointing to the same data.

In Prevayler, however, after a lot of head scratching, I found that
its contents were unchanged on the other side.

After even more head scratching, I found that Prevayler wasn't
changing the data, but a deserialized copy of the data. This is of
course intended, but isn't what I'm personally after, which is
ordinary Java-method-call-like behaviour.

By adding the following lines of code to the source, this is possible:

In Capsule.java:

As an instance member:

	private transient Object _transaction=null; 	
			//Transient so that
			//upon recovery, this
			//field isn't used below:

At the start of the existing constructor:

	_transaction=transaction; //Hold it

And at the beginning of the "executeOn" method:
	
	//Instead of just:
	//Object transaction = deserialize(journalSerializer);
	//Use:

	Object transaction;		
	if(_transaction!=null){ //i.e. capsule has just been
				//constructed, not recovered:
		
		transaction=_transaction;
	}
	else{ 	//i.e. capsule has been recovered (where _transaction
		//would be null because it is transient), or any other
		//case where _transaction is null:
		
		transaction = deserialize(journalSerializer); //as before
	}

//before execution...


Anyone think this is a bad idea? I don't see this version as carrying
any extra risks or side effects. The need to follow the Golden Rule of
Prevayler: that if you want your prevalent system to be fully
recoverable, it must never be manipulated via any reference outside of
the "prevalentSystem" variable provided in transactions' "execute..."
methods, is exactly the same as before. The strict transaction
filtering also exactly the same. The only difference is that
transactions can follow the more expected Java methods behaviour in
terms of things passed in. Recovery only requires the initial snapshot
of the variable, not its final state, right? That final state might be
useful for subsequent things in the app (which it was, in my case).
Any reason why this shouldn't be default in Prevayler?

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