We verified two patterns by changing the keying speed for the same operation test.
※Please imagine the web site where you enter your birthday and name and register for apllication.
case1) Ordinary keying speed(select and enter your birthday with the mouse)
case2) Quick keying speed (Use the tab key on keyboard to move the item of birthday,select the date with down arrow key and input)
In case2,it was confirmed that some user-action were missing in the case of keystrokes quickly.
Even if you move items quickly, since the web request is sent from the client,the user-action I think that it will not be missing.
However,the user-action log is lost due to operation at too high speed what could be considered?
I believe that if you use the tab key approach, but move slowly, you'll see all the actions. The issue is not with using the TAB, but rather with the rapid succession of key strokes and any keystrokes could cause the loss if done fast enough. Can you re-run your tests with the TAB approach but slowly and post your results?