I would imagine that your blood pressure is good and not high. If you do not have to take beta blockers that would be good. Your doctor knows best and if you cut the dose to half and have symptoms let your doctor know right away.
So glad to hear about your excellent treatment at the CC. I have been there 2 times myself, and there are no better docs in the world to treat the heart.
25 mg twice daily is/was below the average dose taken by most people for high bp & pulse rate, post heart attacks, and arrhythmias, etc, I think. Yet, at your tender age, lol, your dose may have been max for you. It depends on how strong your heart was when you began beta blocker therapy (Toprol XL).
I only have one warning and it is; when you have taken a beta blocker, say for over a year or so, your Autonomic nervous system has become adjusted to the overriding affects of the beta blocker. It is used to having the beta blocker control force of contraction (BBs reduce this) and heart rate (BBs decrease heart rate).
Many people experience a "REBOUND) effect when they make drastic changes in their beta blocker dose abruptly. This rebound affect can POSSIBLY cause your BP and heart rate to fluctuate in a rather chaotic fashion.
So, if you do decrease your Toprol XL dose by 50%, record your BP and heart rate at least 4 or 5 times a day, until it becomes stable again. You would logically think that reducing a dose of BB would cause your BP and HR to increase, BUT it can have the opposite affect. I personally have increased my dose of BB by 50%, and my BP and HR went high and was chaotic for awhile, until the autonomic nervous system can become stable again.
I am 56 and I would LOVE to decrease my dose of BB which is Coreg CR, but unfortunately I can't. I have fairly bad side affects to BBs, such as fatigue, exercise intolerance, increased cholesterol and blood sugar, not to mention some embarrassing ones....
My advice is to watch your BP and HR, and "pay attention" to your body in general. You certainly don't need any arrhythmias.
Good luck and you should feel better after reducing the BB, BUT your BP should remain close to 120/70, + or - a few mmhg. Your heart rate is really important and should be around 70 bpm.