Yes, you are interpreting it correctly. I have recently dealt with this.
This article was helpful to me:
Can I have a TXT or SPF record longer than 255 characters?
A notable example of this concept in practice would be the SPF record for cisco.com as of 2/25/2016:
> ;; QUESTION SECTION: ;cisco.com. IN TXT
>
> ;; ANSWER SECTION: cisco.com. 12775 IN TXT
> "926723159-3188410" cisco.com. 12775 IN TXT
> "v=spf1 ip4:173.37.147.224/27 ip4:173.37.142.64/26
> ip4:173.38.212.128/27 ip4:173.38.203.0/24 ip4:64.100.0.0/14
> ip4:72.163.7.160/27 ip4:72.163.197.0/24 ip4:144.254.0.0/16
> ip4:66.187.208.0/20 ip4:173.37.86.0/24" " ip4:64.104.206.0/24
> ip4:64.104.15.96/27 ip4:64.102.19.192/26 ip4:144.254.15.96/27
> ip4:173.36.137.128/26 ip4:173.36.130.0/24 mx:res.cisco.com
> mx:sco.cisco.com ~all" cisco.com. 12775 IN TXT
> "MS=ms65960035"
Just make sure you account for spaces in the records, as you have already indicated.
Also, keep in mind that you need to limit the number of DNS lookups to 10 in your records per the SPF RFC:
SPF implementations MUST limit the number of mechanisms and modifiers
that do DNS lookups to at most 10 per SPF check, including any lookups
caused by the use of the “include” mechanism or the “redirect”
modifier. If this number is exceeded during a check, a PermError MUST
be returned.