Original	Revision
Thus, it is an advantage to create the flow of functions for leaves of the tree hierarchy that allows the designer to analyse the dependencies between functions and thereby obtain a deeper understanding of the task.	Thus, it is an advantage to create the flow of functions for leaves of the tree hierarchy, a flow that allows the designer to analyse the dependences between functions and thereby obtain a deeper understanding of the the task.

The problem here is that it may not be immediately clear to the reader whether the relative clause cross-refers to 'flow' or to 'hierarchy'. The suggested revision shows a way of making the cross-reference clearly.

The following citations show the same structure as the suggested revision: what is the noun from the preceding context to complete each one?

1. Only a quiet and committed dialogue on a common problem, a __________ that respects sovereignty and the pride of countries concerned, will offer any promise of success.
2. We are talking about a different approach to the Divine, an __________ that begins and ends in experience.
3. It was crack cocaine that made the difference - not so much the drug itself as the world in which it is traded, a __________ that is the creation of governments.
4. Sir Iain told the Commons trade and industry select committee: ''Broadband could well form the pivot for the balance of economic success over the next century, a __________ that could tilt one way or another."
5. The government has been making disquieting noises about watering down proposals put forward last year by the pensions law review committee chaired by Professor Roy Goode, a __________ that many believed did not go far enough.
6. Charles had seen eating disorders in his own family (with his sisters Sarah and Diana's problems), a __________ that could only be described as dysfunctional.

Sometimes the noun in this structure is not repeated from the preceding context, but is based on the meaning of the previous context. For example:

The workforce will be reduced by 4,000, a move that will lead to annual cost savings of $500 million.

7. Julia Pollock is legal adviser to the Country Landowners' Association, an __________ that represents more than 50,000 tenant farmers and local authorities.
8. 27.9m mobile phones were shipped worldwide in 1994, a __________ that is forecast to grow to 99.84m by 1999.
9. He was appointed adviser to the Army in 1949, a __________ that he was to hold until 1966 with a short three-year break.
10. On returning to Iran in 1976, he was arrested for taking part in protests in Britain against the Shah, an __________ that convinced him his future lay in Europe.
11. Several European and north American companies are working on Computerised Face Recognition (CFR), a __________ that can scan a crowd at 20 faces a second and match these images against a database of up to 1m photographs.
12. The school mostly consists of `temporary' wooden classrooms now more than 60 years old. They are linked by a narrow, uneven, winding concrete corridor, a __________ that becomes doubly dangerous when water leaks through the roof, as it regularly does.