The pump is a good thing since it helps deliver nutrients to muscles!

Depends on where you are at and where you want to be. Check out www.dropfactorbook.com for a great diet to keep you making progress!

I would get a second opinion. Not only what this idiot saying is wrong, it is far from what the research proves.

Whether natural or not, OVERLOAD is key. This will entail going hard and heavy, both relative terms. Aim to progress each and every workout.

There are no real signs, but starvation mode is a debatable subject unless truly starving. Sporadic refeeds, or as you have carb ups for races, will help!

Honestly mini bands will work your hips and glutes like no other! See this:

Could be a surge of hormone, endorphins....or you just like sex!

NEVER skip leg day--and get used to it by squatting DAILY--see this: https://content.tigerfitness.com/squat-every-day-rehab-health/

I don't feel doing more will lead to more gains. Train every body part as a weak point and they will grow as your genetics allow.

Supersets! Double the work, not double the time!

IMO go with a good MIX like MTS Nutrition Machine Whey. Concentrate is more intact keeping the benefits of whey. The more you filter it the less cool stuff it has. That's why I recommend MTS Whey even though I make an isolate!