'practice has shown that' is correct and usable in written English.
You can use it when you want to express that something has been proven by experience, or to introduce a statement based on experience. For example: "Practice has shown that learning a foreign language is easiest when started at a young age."
However, practice has shown that despite ambitious policies, funding often follows traditional cost-dominated thinking.
Industry practice has shown that technology licensing has an important effect on the remanufacturing of patented products by third parties.
Our exploration practice has shown that new reserves are continuously found each year in spite of the fact that the depression has already been explored for 40 years.
In this case, practice has shown that standard feedback control based on intensive variables has not been very easy to tune and effective in providing consistent operations.
Practice has shown that such an approach does not work at least it does not work without an equal or greater emphasis on the use of condoms.
Putting aside, briefly, the principled objections to this flagship Blairite policy, practice has shown that asbos do little to prevent antisocial behaviour while fast-tracking kids into the criminal justice system.
Lots of underground practices have shown that rock bolts should be installed with enough pretension as soon as the roadway is excavated, the initial separation of rocks can be restrained, and the bolting performance is best (Zhang and Gao 2004; Kang et al. 2007a).
"Past practice has showed that many of the chiefs in the waning years of their career would grudgingly take a position to manage the department at its highest levels, but they never really committed to the tough decision-making that was necessary," he said.
National implementations of the directives that define it should be based on scientific argumentation but practice has showed that they are affected by stakeholders, whose power relations and different normative standpoints have led to very diverse formal and practical implementations of the Network.
However, clinical practice has showed that a description of the X-ray is not enough for proper decision making in orthopaedics and often does not substitute for viewing the actual images [ 8, 9].
Research and practice have shown that compensation works best as a motivator when it comes as soon as possible after the desired behavior.
