The phrase "alleged improvements" is correct and usable in written English.
It can be used when discussing claims or assertions about enhancements or advancements that have not been proven or verified.
Example: "The company has made several alleged improvements to its product, but customers remain skeptical about their effectiveness."
Alternatives: "purported enhancements" or "claimed upgrades".
We're not expecting the city to become Amsterdam overnight, but many of the alleged improvements for cyclists have just made things worse.
In those cases the lands were owned by the United States at the time the alleged improvements were made, for which subsequent purchasers from the government agreed to pay.
Besides, in an industry where investments traditionally take a long time to bear fruit, it is hard to accept that Hayward himself could be held personally responsible for any alleged improvements.
One of the alleged improvements of the PCS 4000 compared to its PBS-IIc predecessor is its special configuration for sensitivity in the high mass range that allows detection of proteins above 100 kDa.
There are also alleged improvements to the recognition itself, now being able to distinguish between twins, providing adjustments for growing children, and the option to save multiple profiles (e.g. one profile with glasses and other without).
My own neighbors have more recently been venting about our 20-block hood having been coined The East Cut last summer (an alleged improvement over its name of Greater Rincon Hill Community Benefit District, though we were satisfied to call it Rincon Hill).
If Barry Bonds were caught on film with a marijuana pipe, people might consider that an improvement in his alleged drug habits.
Taking again the CCPDPP as an alleged model, there is much scope for improvement in practice, with a need for systematic baseline studies and pre-established public health surveillance mechanisms.
It emerged the HSE had served an improvement notice on the company for alleged failures to properly control legionella in its three cooling towers.
To assess the alleged involvement of SCD1 in the fibroblast-triggered improvement of cancer cell migration (Angelucci et al, 2012), both siRNA knockdown and pharmacologic inhibition of SCD1 was performed in cancer cells with a resulted impairment of their migratory ability.
Hundreds of prominent government officials, judges and celebrities who recently redecorated their homes are trembling after being named as alleged customers of a builder suspected of swapping home improvements for large public building contracts.
