MC loading at 47K

No.

 I was thinking last night that results might to some degree depend upon the input capacitance of the first gain stage in your phono section. Both of my phono stages use a cascode input. In a cascode, the gain element that receives the incoming signal is isolated from the anode of a completely discreet separate gain element via a direct connection between the anode of the input tube and the cathode of a second tube. therefore there is very little or none of what is called  Miller capacitance. (Both tubes and transistors exhibit the phenomenon of developing a capacitance between the anode of a tube and the grid. Also between cathode and grid to a lesser degree..) And a transistor has analogous nodes. So if you are using a phono stage with a 12AX7 input tube, for example, The miller capacitance can be quite high, because it is in part a function of the mu which for a 12AX7 is very high. Cartridges connected to the grid of a 12AX7 in a common cathode topology would possibly do better with lower value load resistors. All of the above applies to triodes. Not many tube phono stages use pentodes anyway. Of course, you should keep the cable capacitance as low as possible also.

Most audiophiles have a Pavlovian response to the question of how to load an MC cartridge.  They've been told for so long and from so many sources to use a low value resistor (typically 100R or some resistance that is about 10X the internal resistance of the cartridge) that they cannot accept another idea.  My money is with Ralph and JC and any other of several knowledgeable gurus.  A few years ago, I inadvertently loaded one of my LOMCs at 47K ohms. The experience was a revelation, and I have never looked back.  There's nothing wrong with the typical approach.  Nor is there anything wrong with 47K ohms, and theory says there is a lot that is good about the idea. 

Unlike Uberwaltz's testimony above, I invariably find that 47K gives a slightly more open, extended sense of treble, compared to 100R.  He doesn't say what cartridges he uses.  In my case, it's ZYX Universe (0.24mV output), Koetsu Urushi, Ortofon MC2000, etc. But, as Ralph says, the phono stage itself has most to do with the outcome.