The phrase "allows substantial" is correct and usable in written English.
It can be used when discussing the capacity or capability of something to permit a significant amount or degree of something else.
Example: "The new software update allows substantial improvements in processing speed."
Alternatives: "permits considerable" or "enables significant".
Vojislav Kostunica, the Yugoslav president, this week put forward his vision, which rules out independence and proposes a federation that allows substantial autonomy for the two republics.
In contrast, concrete has a thermal conductivity about 75 times as large (i.e., 4.60 watts per metre per K) and allows substantial heat flux.
Altogether, this approach allows substantial reduction of image acquisition and processing time, while preserving enough user control to ensure the validity of obtained results.
Since law allows substantial rent increases only when apartments are turned over, there can be resentment that older tenants have not only the biggest units but also the cheapest.
Mineralization of N-rich litter from these species allows substantial transfer to companion species and subsequent cycling, thus enabling the development of a self-sustaining ecosystem (Zhang et al. 2001).
If the results from a new trial report that using a newly developed drug/protocol allows substantial survival, the question that can be raised is about the benefits from this drug when patients become critically ill.
Wide wheels allow substantial removal rates.
As altered, the bill now allows for ISPs to be required to block access to sites that allow "substantial" infringement.
We are using new gratings, detectors, and coatings that allow substantial advances in performance.
The young princes were allowed substantial privacy while growing up, but remained uncomfortable in their dealings with the media.
Officers are allowed substantial leeway over how they use force, particularly when it involves killing to save themselves or others.
