>>Desktop app is about 4 times faster than the Web app (server overhead), GUI is much rougher (see attached)
>
>As you often take the time to measure exactly, did you measure which parts slowed down to what percentage or try out running the browser on the machine working as server ?

FAS does that automatically per request, min, avg and max:

avg based on 2,481 user actions from 31 unique users

initializing request 1%
restoring application state for user 0%
restoring form state for user 12%
application 23%
updating menus 0%
saving application state for user 0%
saving form state for user 12%
identifying visual changes 0%
mapping visual changes into HTML 14%
mapping visual changes into XML 4%
cleaning up environment 0%
Internet 16%
Browser 5%
FoxInCloud Application Response Total 100%