I think what the brother is trying to say that too much dhikr will have an effect on any person. Some have experienced this- not just a few tasbee7aat daily but when done in excess, it's not good, as with everything, including optional prayers. If someone spent every second of every minute of every day of their free time praying nawaafil, it would weaken them, and would be classed as extreme. This is where the Hadith comes in: 'Undoubtedly, the Deen is easy (yusr)'* as overburdening ourselves is something we are discouraged from. Again, the Hadith** comes to mind of a person who was standing in the burning heat during the Khutbah, whilst fasting and he'd taken an oath not to seek shade. The Prophet :saws: advised him to complete his fast, and break his oath. << shows that we can't be extreme in these matters.
Just my 2 cents :><:
*Sahih Bukhari Chapter No: 2, Belief
Hadith no: 38
Narrated: Abu Huraira
The Prophet said, "religion is very easy and whoever overburdens himself in his religion will not be able to continue in that way. So you should not be extremists, but try to be near to perfection and receive the good tidings that you will be rewarded; and gain strength by worshipping in the mornings, the nights." (See Fath-ul-Bari, Page 102, Vol 1).
**Imam Malik's Muwatta Chapter No: 22, Vows and Oaths
Hadith no: 6
Narrated:
Yahya related to me from Malik that Humayd ibn Qays and Thawr ibn Zayd adDili both informed him that the Messenger of Allah, may Allah bless him and grant him peace, (and one of them gave more detail than the other),saw a man standing in the sun. The Messenger asked, "What's wrong with him?" The people said, "He has vowed not to speak or to seek shade from the sun or to sit and to fast." The Messenger of Allah, may Allah bless him and grant him peace, said, "Go and tell him to speak, seek shade, and sit, but let him complete his fast." Malik said, "I have not heard that the Messenger of Allah, may Allah bless him and grant him peace, ordered the man in question to do any kaffara. The Messenger of Allah, may Allah bless him and grant him peace, only ordered him to complete that in which there was obedience to Allah and to abandon that in which there was disobedience to Allah."