Yes, that sounds about right. Which I guess would make 4540 rating a bit of a soft cap if your using windsong and always reapply SS when your windsong procs.
On some second looks here, It seemed my initital thoughts of the sacred shield break points is a bit off, they seem to happen slightly faster. From first look, it appeared that the amount ticks you get is how many amount of ticks you get in a 32 second window.
Had a break point happen even earlier now by swapping out some gear, and noticed it break as early as 32.3 seconds
The numbers I posted earlier are probably not entirely correct for breakpoints but should be close.
Looks like the 7 ticks breakpoint is at 30% spell haste exactly ( I got it with 30.06%, it was as close as I could get with my gear )
Theck were art thou!