The 3-car trains were arriving with about a seated load, but 2-car trains were arriving with full standing loads, which suggests they may have been crush loaded at Bloor.
As someone who lives right at the Bloor Station, and often uses the UPX to transit (I avoid peak whenever possible though) I can assure that any load exiting at Weston didn't get on at Bloor, save for a few souls. There's a huge crush getting off at Bloor from Union. At Union, there's two lines formed by staff in peak, one for airport travellers, who load first, then the commuters, and often many have to wait for the next train. Unless they've started to recently, actual body counts aren't made, it's purely down to room left, and a lot of the load is standing.
The 2-car UP trains would not be able to handle the commuter demand from both Weston and Mount Dennis, they're already struggling to handle the demand just from Weston.
For peak, absolutely agreed. Which is why I'm so adamant that two separate services be run along the same present track pathings. Unless someone can indicate otherwise, I'm led to believe that the UPX have their paths signalled at a more intense rate than the the present third track used predominantly for diesel to Mt Pleasant mid-day, and peak in morning, or out evening.
Since I'm led to believe that intervals/headway can be as little as five minutes for the UPX paths (maybe even less) then twice as many emu commuter runs could be added in-between the present 15 min UPX service. These could/would not go to the UPX terminals which would remain as is, as would the DMU service to the airport, but would extend north from the airport spur, either to a GO hub in the airport, where direct 'open ticket' transfer could occur to GO buses (two routes now serve Pearson) and/or continue on to Bramalea, where a plethora of transfers is possible.
At the Union end, either terminating or through-running would occur to perhaps serve Richmond Hill or Unionville. The eastern loop would occur when the next phase of electrification would happen. A commuter service would use a platform in the main station, not the UPX one now used.
Electrification to Mt Pleasant would extend the emus there once the corridor widening would allow.
Since the UPX is the first touted service to be electrified, this concept is 'low hanging fruit' to be taken advantage of. The Georgetown Corridor is woefully underserviced, and yet the demand is clearly there already.