Is uttering "Iyyaka" with a 'hamzat wasl' (connecting hamza) in Al-Fatiha a hidden mistake (lahn khafi)? And is overemphasizing the 'shaddah' (doubling) on letters that have it, such as in "Ad-Dalleen," to the extent that it prolongs the time of their pronunciation, considered an error and an obvious mistake (lahn jali)?

The difference between hamzat al-wasl (connecting hamza) and hamzat al-qat' (cutting hamza) becomes apparent during the flow of speech. The hamzat al-qat' in Al-Fatihah does not drop; dropping it is a mistake that invalidates the prayer if not rectified. Exaggerating the emphasis on a mushaddad (doubled) letter is disliked. As for one who experiences waswasah (whispers/obsessive thoughts) regarding the pronunciation of letters, they should ignore these whispers and focus on contemplating the meanings of the Qur'an and experiencing khushu' (devotion/humility) in prayer. Indeed, waswasah regarding the articulation points of letters is one of Satan's traps.