I know this thought process well. I used to be one of those developers :). But I have seen the light. I have been reborn. I know that it is important to get testers input on products upfront. And actually it is becoming more important now than ever before.
With RIA (Web 2.0) technologies there are many different choices that developers can make. Should they use Flex, Silverlight, AJAX, etc... If they use AJAX, which frameworks should they use. If Silverlight then what type of back end communication are they going to use?
Let's just take AJAX as an example. There are hundreds of frameworks out there. Some are popular and common frameworks but most are obscure or one off frameworks. Developers like to make decisions on what will make their life easier and what is cool. But what happens if their choices can't be performance tested? Maybe the performance team doesn't have the expertise in-house, or maybe their testing tools don't support the chosen framework. What happens then?
I can tell you that many times the apps get released without being tested properly and they just hope for the best. It's a great solution. I like the fingers crossed method of releasing apps.
How could this situation be avoided? Simply include the performance testing group upfront. Testing is a major cog in the application life cycle. They should be included at the beginning. I'm not talking about testing earlier in the cycle (although that is important and it should be done). I'm talking about getting testing involved in architecture and development discussions before development takes place.
If developers and architects knew up front that certain coding decisions would make it hard or impossible to performance test, then maybe they would choose other options for the application development. Many businesses would not want to risk releasing an application if they knew that it could be tested properly. But when they find out too late, then they don't have a choice except to release it (the finger crossing method).
If the performance team knew upfront that they couldn't test something because of skills or tools, then at least they would have a heads-up and they could begin planning early for the inevitable testing. Wouldn't it be nice to know what you are going to need to performance test months in advance? No more scrambling at the 11th or 12th hour.
Think about this. If testing was invloved or informed upfront, then maybe they, along with development, could help push standards across development. For example, standardizing on 1 or 2 AJAX frameworks would help out testing and development. It will make the code more maintainable because more developers will be able to update it and it will help ensure that the application is testable.