[Building Sakai] Questions about EntityEncoding maxLevel

[Marc Savitsky]

I am doing some work on a contentEntityProvider in sakai2.8 and found 
that I am coming up against a limit in the depth within my entity that 
is output.

It seems that when transcoders are registered (in EntityEncodingManager) 
the JSON transcoder is set a maxLevel to descend the object.  There is 
code in EntityBrokerManagerImpl to allow this to be between 5 and 25.  
No max level is set in the xml and html transcoders, so these rely on a 
default, which seems to be set to 7.

I can see that a max level may be useful if the entity loops but:
Why is it necessary to have a different level depending on the output 
format?
Is the absence of configurable levels for xml and html an oversight?
Wouldn't it be better to configure the level by entity provider rather 
than across the board?
What is the effect on performance if the max level is set to 25?

many thanks
Marc