What's the purpose of a 'MIDI remote control' (with pedal?) And what is it supposed to do?
MIDI contollers (in regards to amplifiers) are usually a way of activating switchable circuits on an amp. For example, channels, reverb, FX Loop and so on.
A MIDI controller can have alot of switches running into one port, whereas a standard footswitch will have a max of 3 (thats the most i've ever seen anyway) and to add more you would need another port and footswitch.

My Z-5 is a MIDI footswitch and has 6 buttons running into one port. On the back of the amp there are two inputs for analogue footswitches.
Main Gear:

Santiago S3 Spanish Classical
PRS CE22 Mahogany
Mesa/Boogie F-50 combo w/ G12K-100
Teese RMC Wizard Wah
Rothwell Switchblade
Ibanez FL-9
Visual Sound Liquid Chorus V2