"has often revealed" is correct and usable in written English.
It can be used to indicate that something has been frequently or regularly disclosed or shown. Example: The company's financial reports has often revealed a steady increase in profits over the past few years.
Instead, he has often revealed music anew.
The government's shortsighted attitude has often revealed itself.
However, critical analysis of the data has often revealed errors and partially explained the lack of efficacy, opening the way to a refinement in designing pre-clinical studies.
This microscopy-based method has often revealed a high cell-to-cell variability in expression levels, which has in turn led to a growing interest in investigating the biological significance of gene expression noise.
Federer has often revealed that the key factor in maintaining his longevity has been simply enjoying his job.
The use of mixed methods in a single study has often revealed inconsistencies between the data collected using different instruments, but not much attempt has been made to find out why results are inconsistent.
Perhaps Mr. Russell, whose movies have often revealed a puckish, not to say freakish, taste in humor, is also complicit.
Her dispatches from the front lines of major ethnic and religious battles have often revealed Africa and Asia to be fracturing along religious, economic, and ethnic divides.
Empirical studies of ostensibly bureaucratic organizations have often revealed a rich informal life within them that is at odds with the formal chain-of-command depictions.
New programs since the 1960s have often uncovered the unknown unknowns, usually the hard way early flights of new systems have often revealed problems of which the designers were unaware.
However, clinical studies addressing this question have often revealed conflicting data, perhaps because of inherent difficulties in accurately monitoring the dynamics of apoptosis in vivo [reviewed in 46].
