Mark really isn't the best training partner. He is normally 5-8 minutes late - although may also arrive 40 minutes EARLY and wonder where you were. (Never more than 8 minutes.) The best part of Mark is that when he works - he really works. Having a training partner who is NOT a triathlete is great. Who cares what race you are doing or what your "speed" is! How fit are you at THIS task? Kinda a cross fit mentality. If I grab 135 lbs. for walking lunges, Mark grabs 140. If he cannot do the same weight as me, Mark makes sure that my form is spot on and will openly (and loudly) mock me in the gym.
When people ask me what they should do to get better at triathlon (or any sport) my answer remains the same as it did years ago:
1) Find a group that will challenge you. A group that won't except your bullshit excuses for stopping short, showing up late, and failing to "put out" (effort into the session).
2) Work with people who are better than you are. I swim with people who are faster than I am. I ride with people who are stronger. I run with people who LITERALLY run loops around me during a long run (their easy run).
3) Seek out the best in exercise and recovery and ask them questions. They are just people too. I'm no longer amazed when a "big name" sends me an email, tweet, Facebook message or phone call after I ask them a question. "When the student is ready the teacher will appear." - Confucius
4) Show up. Yes, it's that simple. Show up to every session and try. One day you may just find yourself at the Ironman World Championship pier and wonder, "How did I get here?" One of my clients had that moment when he WON the USAT National Long Distance Duathlon Championship (M30-34). He still doesn't believe he really did it.
5) Have a positive mental attitude. 99% of your worries won't come true. Stop thinking about the negative and wonder "what if...." There are tons of people who will tell you you "can't" or that "you suck". Ignore them. Concentrate on what you can do and do it to the best of your ability. Find and hang out with positive people. Stay away from the negative people. They are a giant energy vacuum. Remember who told you 'you can't' and enjoy "shoving it up their ass" when you do it. One of my HS running coaches once told me, "You'll never be a good athlete." I'll never forget the look on his face when I told him I had just returned from NCAAs or when I saw him in O'Hare the moment I got off the plane from Kona with a giant silver medal in my hands. PRICELESS!!!
6) Follow the plan. Stick to your plan. Ignore the group and listen to your wattage and heart rate monitor (or pulse if you are in the pool). If it sounds too ambitious, it probably is. Error on the side of caution and FOCUS on your "A" race. Especially if you are doing an Ironman race - LESS is more. Most fast guys I know, when they do Ironman, they do only four races in a year FOUR. Including whatever Ironman they are doing. Choose them well.
Now... get to work. It's not complex, but it also isn't easy.
It ain't rocket surgery.