Confusion about ISR

Hello,

me and my group members were pondering if it is really necessary to add a photon and the respective cuts when we want to generate the ISR process in whizard or is just switching on ISR sufficient? We were looking at the ISR plots for mu+mu- > XX for both with and without photon + cuts needed to select the ISR photon. It appears that the plot without photon+cuts retains a similar shape to the bare process - just with lower values as opposed to the one with photon+cuts. We are confused about what we should stick with. Thank you for your help. This was the script used for photon+cuts,

model = NewBP1ufo (ufo)
betaH = 1.47112767
Ma = 325 GeV
WAh2 = 2.11606063 GeV
Wh3 = 2.967256 GeV
Wh2 = 0.002660598 GeV
process mmaa = e2 , e2bar => a, a, A

compile

beams = e2 , e2bar => isr

!beams_pol_density = @(-1), @(-1)
!beams_pol_fraction = 80%, 20%
?fatal_beam_decay = false
isr_q_max = 20 GeV
isr_alpha = 1./137.
epa_q_min = 5 GeV
epa_x_min = 0.01

$description = "mumuxx with isr"
$x_label = "$\sqrt{s}$/GeV"
$y_label = "$\sigma(s)$/fb"
x_min = 800 GeV
x_max = 1000 GeV

cuts = let subevt @meA = select if Index > 2 [A] in
  all E > 10 GeV [@meA] and all Theta > 7 degree [@meA]

$title = "mumuxx with ISR"
plot mumuxxisr {$draw_options = "withcolor red"}

scan sqrts = (800 GeV => 1000 GeV /+ 10 GeV) {
 integrate (mmaa) {iterations = 5:50000, 3:100000}
 record mumuxxisr(sqrts, integral (mmaa))
 }

compile_analysis { $out_file = "mumuxxisr" }