The phrase "flexible to allow" is correct and usable in written English.
It can be used when describing something that is adaptable or adjustable in order to permit certain actions or conditions.
Example: "The new software is flexible to allow users to customize their settings according to their preferences."
Alternatives: "adaptable to permit" or "versatile enough to enable".
"Policies need to be sufficiently flexible to allow access to highly skilled labour and unskilled.
This multi-stage pump design was sufficiently flexible to allow adaptation to a variety of applications.
Scheduling is flexible to allow you to set up a time when all of your employees can attend.
Since then there has been an increasing realization that the regulations needed to be more flexible to allow flying to continue in unusual conditions, he said.
Such a system must be robust enough to efficiently store large amounts of data, and flexible to allow users to manipulate a wide variety of information.
An extra parameter is needed to make the model sufficiently flexible to allow it to be applied to porous foods with a range of different structures.
To respond effectively to this demand, manufacturers need to ensure that their manufacturing practices are sufficiently flexible to allow them to achieve rapid product development.
The design is flexible to allow the substitution of different analysis modules and extensible to allow the inclusion of additional hockey situations.
He said: "It is our view that the choice of subjects should be more flexible to allow schools to have greater freedom in how they tailor the curriculum to the individual needs of each pupil.
He said the union is also lowering certain initiation fees and making its eligibility requirements more flexible to allow firms with as few as one or two employees, to join the union.
Denis Donoghue, the critic and literary scholar, wrote of the book admiringly as "an eccentric and yet concentric work of art, a work sufficiently flexible to allow a digression every 10 pages or so".
