When DC United was in town, I was chatting with one of their associates about their recent losses. They weren't in full panic mode yet, but the signs weren't looking good. We talked about how the end of the season could wear teams down, especially if they had to play extra games.
I shared my theory that it was unfair for MLS teams to be involved in international competition like the CONCACAF Champions League without some sort of assistance to handle the extra burden. I don't advocate raising the salary cap for teams, but I do think that there should be expanded rosters exclusive for those competitions, outside of the MLS cap. Five or even three supplemental players could make a big difference. There could be a set cap for those temporary additions. Teams in Mexico allow for roster expansion for Copa Libertadores participation. It just makes practical sense.
It's almost disrespectful to compete in tournaments with so many top players held back. It's completely understandable, given that DC is now struggling to make the playoffs. Yet that's not really competing in a tournament any more, it's merely showing up as a shadow of a true team.
Anyway, the conversation wound up with some speculation as to why MLS administration hasn't acted to bolster the teams that represent the league internationally in any way. They're just expected to take on the extra work and effort with no help.
On the other hand, I do see the value in giving young players real games that are against a high level of competition. DC's youth actually represented quite well against Cruz Azul.