Re: Breaking Bad Season 4 Premiere Sun 10pm AMC (Spoilers!)
I don't see it as lazy writing. They planted this seed in season four. Jesse already first suspected Huell lifted the cigarettes off him when he accused Walt of poisoning Brock, so knowing he lifted his pot this time was a sensible conclusion for him to reach.
Remember that Jesse even told Walt he thought Heull took the ricin when he went into Saul's office. This just confirmed his suspicions.
"No matter how good you are, you're going to lose one-third of your games. No matter how bad you are you're going to win one-third of your games. It's the other third that makes the difference." ~Tommy Lasorda