Variable Persistence in Looping Custom Transformers

In regards to Linked Looping Custom Transformers, is there a way for Variables to persist through iterations? Currently the Global Variables persist per feature even though FME seems to process a single iteration at a time rather than perform all iterations for a single feature before going to the next feature.

 

 

What i'm seeing is:

 

Iteration 1:

 

1st feature goes in, global variable set to a. Needs to be looped.

 

2nd feature goes in, variable appended to a, b. Needs to be looped.

 

3rd feature goes in, variable appended to a, b, c. Needs to be looped

 

 

Iteration 2: 

 

1st feature goes through loop, yet variable's value is a.

 

2nd feature goes through loop, its variable value is b.

 

 

This is likely following the flow of features yet the log file is extremely confusing as it shows the processing via iterations rather than tracing a single feature through all iterations.