Clarification on Datatypes Spec

Hallo NG,
 
I have got the following question, that refers to the Datatypes Spec
 
The canonical representation of float is defined as follows:
 
3.2.4.2 Canonical representation
The canonical representation for float is defined 
by prohibiting certain options from the Lexical 
representation (§3.2.4.1). Specifically, the 
exponent must be indicated by "E". 
Leading zeroes and the preceding optional "+" sign 
are prohibited in the exponent. For the mantissa, 
the preceding optional "+" sign is prohibited and 
the decimal point is required. For the exponent, 
the preceding optional "+" sign is prohibited. 
Leading and trailing zeroes are prohibited subject 
to the following: number representations must be 
normalized such that there is a single digit to the 
left of the decimal point and at least a single digit 
to the right of the decimal point. 

If I take the following two sentences out of it:
 
3.2.4.2 Canonical representation
.... 
Leading zeroes and the preceding optional "+" sign 
are prohibited in the exponent. ...
For the exponent, the preceding optional "+" sign is prohibited. 
....
 
Question: This definition seems to mention that the
"preceding optional "+" sign is prohibited" two times.
 
Is this intentionally? If this is the case, please tell me why?
 
See you all
 
Rainer Becker