Pre-TS Blackbeard didnt lose situationally before he won lol.
- He beat Ace
- He became a Shichibukai
- He broke into Impel Down
- He staged a breakout, defeated Magellan and gained 5 additional members.
- He orchestrated a war between WB and Marines
- He killed and stole WBs powers.
- He became a Yonko.
Losing to Law or losing to Garp in either scenario is not remotely comparable to the above. It doesnt make him a master planner, it makes him randomly lucky if these events lead to something better.