The planes didn't have on board radar to confuse. The planes could collide with the baloons or their tethers (but either seems rather unlikely), so what exactlly was their role? As they can't have been cheap to make and maintain. So they must have had a significant role that I cannot see.
Asking after watching the BBC documentary series - Blitz: The Bombs that Changed Britain.
Facinating series, single bombs (among the thousands and thousands dropped) had a massive impact on Britain, well beyound the local damage - changes to social support / welfare etc. that can be tracked back to the influence resulting from a single bomb.
The lower a bomber could fly, the more precisely it could hit a target; the most accurate German aircraft were the Junkers 87 Stuka dive bombers that dived steeply from high altitude towards their target, typically releasing bombs at a height of around 1,000 - 2,500 feet. The purpose of barrage balloons was to force enemy aircraft to fly higher to avoid their cables; with balloons at a height of 5,000 feet dive bombing was extremely difficult, and level bombers had to fly higher with a resultant loss in accuracy. Aircraft becoming tangled in the cables was a bonus, and though unusual was not entirely unknown. "Balloons and anti-aircraft fire, always valuable deterrents to low-level bombing, sometimes scored more tangible successes. In February and March [1941] at least seven German aircraft crashed after striking balloon-cables in various parts of the United Kingdom." (Basil Collier, The Defence of the United Kingdom).
Overall, as Anthony Price puts it in Britain's Air Defences, 1939-45, "The purpose of the balloons was to protect targets by preventing accurate attacks by low-flying aircraft or dive-bombers. In this, they were brilliantly successful. Although they brought down few German aircraft - less than 30 during the entire war - there is no recorded instance of low-flying aircraft or dive-bombers making a deliberate attack on a target protected by balloons."
The planes could collide with the baloons or their tethers (but either seems rather unlikely)
During the Spanish Civil War and the invasions of Poland, France and the Low Counties, the Luftwaffe had made extensive use of dive-bombers, in particular the Ju-87 Stuka. Although they carried a smaller payload than other bombers, dive-bombers were used to devastating effect thanks to their ability to evade AA fire and achieve accurate bombardment of targets from a low altitude. Barrage balloons were deployed over Britain with precisely this in mind: the risk of collision with a balloon or tether, and the simple blocking effect of the balloon over a target was specifically designed to hamper the efforts of the German dive-bombers that were fully expected to be leading the Luftwaffe's attack on Britain. While bombers could easily avoid the balloons by flying at high altitude, this left them far more vulnerable to AA fire, and also limited the accuracy of their bombardment.
Of course, in practice, dive-bombers require a fair degree of air superiority to operate effectively, and the failure of the Luftwaffe to ground the RAF meant that dive-bombers were rarely employed to their true purpose during the Battle of Britain, but the balloons continued to be used as a deterrent.