Don't Trust Youtube Reason ??? of ???: The setting was already optimized

Have you seen the promise on Youtube before: "change one setting and your internet connection speed will be 3 times faster (or more)!" 

Hint; it only shows that dramatic increase because they had ruined their previous settings for force the speed down, in order to show you the "dramatic" differences, like going from 150 mpbs to 450 Mbps. 

TheTechieGuy was guilty of this, and so was TheDealGuy, who basically relayed the same lesson. 

What did they do? They optimized the MTU. 

Optimizing an MTU is a legitimate "hack". Basically, it's to coordinate between the router and the client. Router basically says "I can handle this many bytes at a time". The client can send a smaller packet, but that would be "under-utilizing" the router. So to optimize the settings, one should set the MTU on the client to "match" the router's allowable size. 

I had recently swapped out my older AC router for a more advanced AC2600 router from D-link. I know I didn't change the MTU on router OR client. 

Why not do the test? Who doesn't want more speed? 

So I did the test. I got the result of 1472. 

C:\WINDOWS\system32>ping www.yahoo.com -f -l 1474

Pinging new-fp-shed.wg1.b.yahoo.com [74.6.231.21] with 1474 bytes of data:

Packet needs to be fragmented but DF set.

Packet needs to be fragmented but DF set.

Packet needs to be fragmented but DF set.

Packet needs to be fragmented but DF set.

Ping statistics for 74.6.231.21:

    Packets: Sent = 4, Received = 0, Lost = 4 (100% loss),

C:\WINDOWS\system32>ping www.yahoo.com -f -l 1472

Pinging new-fp-shed.wg1.b.yahoo.com [74.6.231.21] with 1472 bytes of data:

Reply from 74.6.231.21: bytes=1472 time=79ms TTL=48

Reply from 74.6.231.21: bytes=1472 time=79ms TTL=48

Reply from 74.6.231.21: bytes=1472 time=79ms TTL=48

Reply from 74.6.231.21: bytes=1472 time=78ms TTL=48

Ping statistics for 74.6.231.21:

    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),

Approximate round trip times in milli-seconds:

    Minimum = 78ms, Maximum = 79ms, Average = 78ms

Add 28 to that, the optimal MTU size is 1500. 

So I checked the Win10 MTU size via the same cmd (administrator) prompt  (use netsh interface ipv4 show subinterfaces)... It is ALREADY set to 1500. 

So it's pretty obvious that if the DEFAULT router settings are already optimized pretty much, any of those "change one setting" and show dramatic speed increase is rigged. 

And now you know... Don't trust Youtube advice on something important. Study what they have to say and why they say it, UNDERSTAND the actual advice, and see if it really works for yourself. 

And don't be surprised if it doesn't.