Comment by xelamonster

Either you're making so much you could comfortably cut back on work for lower pay, or you're being too hard on yourself in feeling that every minute of your work day must be dedicated to directly producing business results. If expectations are so high that you need to push to the point of mental exhaustion every day to meet deadlines that's not a healthy work environment.

Your employer benefits from you expanding your knowledge even in areas not immediately applicable to the work in front of you. Your output will be improved if you're exposed to fresh ideas and working at a sustainable pace where you don't feel overwhelmed. If your employer doesn't understand that I'd consider finding a better one.

Lots of places are happy for you to take time for training during work hours. Many are even willing to pay for it.