There wouldn't be a "noticeable blurp" because a bubble of air in the line will simply cause the engine to go lean for a second, assuming that the fuel in the line is replenished soon enough. If not the engine would go lean, then quit.
Then explain why an engine running on the ground that for one reason or another is getting air bubbles in the fuel line runs noticeably erratic. At any rate, I would consider "going lean for a second" very noticeable.