Well sure, old rules, new rules - as long as they kept giving you the necessary breaks, you could be at work indefinitely, I guess.

Hypothetical 7 day trip:
Day 1: report 1900, 5 hour FDP, 14 hour layover
Day 2: 10 hour FDP, 14 hour layover
Day 3: 10 hour FDP, 14 hour layover
Day 4: 10 hour FDP, 14 hour layover
Day 5: 10 hour FDP, 11 hour layover
Day 6: 10 hour FDP, 11 hour layover
Day 7: 5 hour FDP. Block in at 1300

138 hours from report to block in. 60 total FDP hours. No 30 hour breaks, no 24 hour breaks.
At 1300 on day 7 you still had 30 hours off in the previous 168.
Legal under 117. Not legal under current FAR's
Yes, it's pushed right at the limit. No, we would probably never actually see a trip like this (never say never?). But a hypothetical trip like this is a good way to get a feel for what is possible under the new rules.