let C be Simple_closed_curve; for n being Element of NAT st n is_sufficiently_large_for C holds
Y-SpanStart C,n < width (Gauge C,n)
let n be Element of NAT ; ( n is_sufficiently_large_for C implies Y-SpanStart C,n < width (Gauge C,n) )
A1:
len (Span C,n) > 1
by GOBOARD7:36, XXREAL_0:2;
assume A2:
n is_sufficiently_large_for C
; Y-SpanStart C,n < width (Gauge C,n)
then A3:
(Span C,n) /. 1 = (Gauge C,n) * (X-SpanStart C,n),(Y-SpanStart C,n)
by JORDAN13:def 1;
[(X-SpanStart C,n),(Y-SpanStart C,n)] in Indices (Gauge C,n)
by A2, JORDAN11:8;
hence
Y-SpanStart C,n < width (Gauge C,n)
by A2, A1, A3, Th26; verum